Positioning assistance data procedures

ABSTRACT

Disclosed are techniques for performing positioning operations. In an aspect, a user equipment (UE) transmits, to a positioning entity, a request for positioning assistance data message, the request for positioning assistance data message identifying a serving cell of the UE and one or more neighboring cells of the UE with which the UE is attempting to perform a positioning procedure, and receives, from the positioning entity, a positioning assistance data message in response to the request.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present Application for Patent claims the benefit of U.S.Provisional Application No. 62/806,377, entitled “POSITIONING ASSISTANCEDATA PROCEDURES,” filed Feb. 15, 2019, assigned to the assignee hereof,and expressly incorporated herein by reference in its entirety.

INTRODUCTION 1. Technical Field

Various aspects described herein generally relate to wirelesscommunication systems, and more particularly, to positioning assistancedata procedures in New Radio.

2. Background

Wireless communication systems have developed through variousgenerations, including a first-generation analog wireless phone service(1G), a second-generation (2G) digital wireless phone service (includinginterim 2.5G and 2.75G networks), a third-generation (3G) high speeddata, Internet-capable wireless service and a fourth-generation (4G)service (e.g., Long Term Evolution (LTE) or WiMax). There are presentlymany different types of wireless communication systems in use, includingcellular and personal communications service (PCS) systems. Examples ofknown cellular systems include the cellular analog advanced mobile phonesystem (AMPS), and digital cellular systems based on code divisionmultiple access (CDMA), frequency division multiple access (FDMA), timedivision multiple access (TDMA), the Global System for Mobile access(GSM) variation of TDMA, etc.

A fifth generation (5G) mobile standard, also referred to as New Radio(NR), calls for higher data transfer speeds, greater numbers ofconnections, and better coverage, among other improvements. The 5Gstandard, according to the Next Generation Mobile Networks Alliance, isdesigned to provide data rates of several tens of megabits per second toeach of tens of thousands of users, with 1 gigabit per second to tens ofworkers on an office floor, for example. Several hundreds of thousandsof simultaneous connections should be supported in order to supportlarge sensor deployments. Consequently, the spectral efficiency of 5Gmobile communications should be significantly enhanced compared to thecurrent 4G standard. Furthermore, signaling efficiencies should beenhanced and latency should be substantially reduced compared to currentstandards.

To support position estimations in terrestrial wireless networks, amobile device can be configured to measure and report the observed timedifference of arrival (OTDOA) or reference signal timing difference(RSTD) between reference radio frequency (RF) signals received from twoor more network nodes (e.g., different base stations or differenttransmission points (e.g., antennas) belonging to the same basestation). The mobile device can also be configured to report time ofarrival (ToA) of RF signals. With OTDOA, when the mobile device reportsthe time difference of arrival (TDOA) between two network nodes, thelocation of the mobile device is then known to lie on a hyperbola withthe locations of the two network nodes as the foci. Knowledge of theTDOAs between multiple pairs of network nodes allows a positioningentity (e.g., a location server) to solve for the mobile device'sposition as the intersections of the hyperbolas.

Round-trip time (RTT) is another technique for determining a position ofa mobile device. RTT is a two-way RF messaging technique in which atransmitter (e.g., the network node) reports, to a positioning entity,the transmit-to-receive time difference between transmitting a referenceRF signal to a receiver (e.g., the mobile device) and receiving aresponse RF signal from the receiver, and the receiver reports, to thesame positioning entity, the receive-to-transmit time difference betweenreceiving the reference RF signal from the transmitter and sending theresponse RF signal to the transmitter. The positioning entity (e.g., alocation server) computes the distance between the mobile device and thenetwork node based on these measurements. The location of the mobiledevice is then known to lie on a circle with a center at the networknode's position. Reporting RTTs with multiple network nodes allows thepositioning entity to solve for the mobile device's position asintersections of the circles.

SUMMARY

This summary identifies features of some example aspects, and is not anexclusive or exhaustive description of the disclosed subject matter.Whether features or aspects are included in, or omitted from thissummary is not intended as indicative of relative importance of suchfeatures. Additional features and aspects are described, and will becomeapparent to persons skilled in the art upon reading the followingdetailed description and viewing the drawings that form a part thereof.

In an aspect, a method for performing positioning operations at a userequipment (UE) includes transmitting, by the UE to a positioning entity,a request for positioning assistance data message, the request forpositioning assistance data message identifying a serving cell of the UEand one or more neighboring cells of the UE with which the UE isattempting to perform a positioning procedure, and receiving, at the UEfrom the positioning entity, a positioning assistance data message inresponse to the request.

In an aspect, a method for performing positioning assistance operationsat a positioning entity includes receiving, from a UE, a request forpositioning assistance data message, the request for positioningassistance data message identifying a serving cell of the UE and one ormore neighboring cells of the UE with which the UE is attempting toperform a positioning procedure, and transmitting, to the UE, apositioning assistance data message in response to the request.

In an aspect, a UE includes a memory, at least one transceiver, and atleast one processor communicatively coupled to the memory and the atleast one transceiver, the at least one processor configured to: causethe at least one transceiver to transmit, to a positioning entity, arequest for positioning assistance data message, the request forpositioning assistance data message identifying a serving cell of the UEand one or more neighboring cells of the UE with which the UE isattempting to perform a positioning procedure, and receive, from thepositioning entity via the at least one transceiver, a positioningassistance data message in response to the request.

In an aspect, a positioning entity includes a memory, a communicationdevice, and at least one processor communicatively coupled to the memoryand the communication device, the at least one processor configured to:receive, from a UE via the communication device, a request forpositioning assistance data message, the request for positioningassistance data message identifying a serving cell of the UE and one ormore neighboring cells of the UE with which the UE is attempting toperform a positioning procedure, and cause the communication device totransmit, to the UE, a positioning assistance data message in responseto the request.

In an aspect, a UE includes means for transmitting, to a positioningentity, a request for positioning assistance data message, the requestfor positioning assistance data message identifying a serving cell ofthe UE and one or more neighboring cells of the UE with which the UE isattempting to perform a positioning procedure, and means for receiving,from the positioning entity, a positioning assistance data message inresponse to the request.

In an aspect, a positioning entity includes means for receiving, from aUE, a request for positioning assistance data message, the request forpositioning assistance data message identifying a serving cell of the UEand one or more neighboring cells of the UE with which the UE isattempting to perform a positioning procedure, and means fortransmitting, to the UE, a positioning assistance data message inresponse to the request.

In an aspect, a non-transitory computer-readable medium storingcomputer-executable instructions includes computer-executableinstructions comprising at least one instruction instructing a UE totransmit, to a positioning entity, a request for positioning assistancedata message, the request for positioning assistance data messageidentifying a serving cell of the UE and one or more neighboring cellsof the UE with which the UE is attempting to perform a positioningprocedure, and at least one instruction instructing the UE to receive,from the positioning entity, a positioning assistance data message inresponse to the request.

In an aspect, a non-transitory computer-readable medium storingcomputer-executable instructions includes computer-executableinstructions comprising at least one instruction instructing apositioning entity to receive, from a UE, a request for positioningassistance data message, the request for positioning assistance datamessage identifying a serving cell of the UE and one or more neighboringcells of the UE with which the UE is attempting to perform a positioningprocedure, and at least one instruction instructing the positioningentity to transmit, to the UE, a positioning assistance data message inresponse to the request.

Other objects and advantages associated with the aspects disclosedherein will be apparent to those skilled in the art based on theaccompanying drawings and detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are presented to aid in the description ofexamples of one or more aspects of the disclosed subject matter and areprovided solely for illustration of the examples and not limitationthereof:

FIG. 1 illustrates an exemplary wireless communications system inaccordance with one or more aspects of the disclosure;

FIGS. 2A and 2B illustrate example wireless network structures inaccordance with one or more aspects of the disclosure;

FIGS. 3A to 3C are simplified block diagrams of several sample aspectsof components that may be employed in wireless communication nodes andconfigured to support communication as taught herein.

FIG. 4 illustrates a conventional LTE positioning protocol (LPP) callflow between the wireless mobile device and the location server forperforming positioning operations.

FIGS. 5A and 5B illustrate exemplary call flows between a UE and alocation management function (LMF) for performing positioningoperations, according to aspects of the disclosure.

FIG. 6 illustrates an exemplary call flow between a UE and a networknode for performing positioning operations, according to aspects of thedisclosure.

FIG. 7 illustrates a conventional LPP acknowledgment call flow between aUE and a location server.

FIG. 8 illustrates a conventional LPP retransmission call flow between aUE and a location server.

FIG. 9 illustrates a conventional LPP periodic assistance data transfercall flow between a UE and a location server.

FIG. 10 illustrates an exemplary method of providing assistance datafrom an LMF to a UE, according to aspects of the disclosure.

FIGS. 11 and 12 illustrate exemplary methods for providing positioningassistance data to a UE, according to aspects of the disclosure.

DETAILED DESCRIPTION

Aspects of the disclosure are provided in the following description andrelated drawings directed to various examples provided for illustrationpurposes. Alternate aspects may be devised without departing from thescope of the disclosure. Additionally, well-known elements of thedisclosure will not be described in detail or will be omitted so as notto obscure the relevant details of the disclosure.

The words “exemplary” and/or “example” are used herein to mean “servingas an example, instance, or illustration.” Any aspect described hereinas “exemplary” and/or “example” is not necessarily to be construed aspreferred or advantageous over other aspects. Likewise, the term“aspects of the disclosure” does not require that all aspects of thedisclosure include the discussed feature, advantage or mode ofoperation.

Those of skill in the art will appreciate that the information andsignals described below may be represented using any of a variety ofdifferent technologies and techniques. For example, data, instructions,commands, information, signals, bits, symbols, and chips that may bereferenced throughout the description below may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof, depending inpart on the particular application, in part on the desired design, inpart on the corresponding technology, etc.

Further, many aspects are described in terms of sequences of actions tobe performed by, for example, elements of a computing device. It will berecognized that various actions described herein can be performed byspecific circuits (e.g., application specific integrated circuits(ASICs)), by program instructions being executed by one or moreprocessors, or by a combination of both. Additionally, the sequence(s)of actions described herein can be considered to be embodied entirelywithin any form of non-transitory computer-readable storage mediumhaving stored therein a corresponding set of computer instructions that,upon execution, would cause or instruct an associated processor of adevice to perform the functionality described herein. Thus, the variousaspects of the disclosure may be embodied in a number of differentforms, all of which have been contemplated to be within the scope of theclaimed subject matter. In addition, for each of the aspects describedherein, the corresponding form of any such aspects may be describedherein as, for example, “logic configured to” perform the describedaction.

As used herein, the terms “user equipment” (UE) and “base station” arenot intended to be specific or otherwise limited to any particular radioaccess technology (RAT), unless otherwise noted. In general, a UE may beany wireless communication device (e.g., a mobile phone, router, tabletcomputer, laptop computer, tracking device, wearable (e.g., smartwatch,glasses, augmented reality (AR)/virtual reality (VR) headset, etc.),vehicle (e.g., automobile, motorcycle, bicycle, etc.), Internet ofThings (IoT) device, etc.) used by a user to communicate over a wirelesscommunications network. A UE may be mobile or may (e.g., at certaintimes) be stationary, and may communicate with a radio access network(RAN). As used herein, the term “UE” may be referred to interchangeablyas an “access terminal” or “AT,” a “client device,” a “wireless device,”a “subscriber device,” a “subscriber terminal,” a “subscriber station,”a “user terminal” or UT, a “mobile terminal,” a “mobile station,” orvariations thereof. Generally, UEs can communicate with a core networkvia a RAN, and through the core network the UEs can be connected withexternal networks such as the Internet and with other UEs. Of course,other mechanisms of connecting to the core network and/or the Internetare also possible for the UEs, such as over wired access networks,wireless local area network (WLAN) networks (e.g., based on IEEE 802.11,etc.) and so on.

A base station may operate according to one of several RATs incommunication with UEs depending on the network in which it is deployed,and may be alternatively referred to as an access point (AP), a networknode, a NodeB, an evolved NodeB (eNB), a New Radio (NR) Node B (alsoreferred to as a gNB or gNodeB), etc. In addition, in some systems abase station may provide purely edge node signaling functions while inother systems it may provide additional control and/or networkmanagement functions. A communication link through which UEs can sendsignals to a base station is called an uplink (UL) channel (e.g., areverse traffic channel, a reverse control channel, an access channel,etc.). A communication link through which the base station can sendsignals to UEs is called a downlink (DL) or forward link channel (e.g.,a paging channel, a control channel, a broadcast channel, a forwardtraffic channel, etc.). As used herein the term traffic channel (TCH)can refer to either an UL/reverse or DL/forward traffic channel.

The term “base station” may refer to a single physicaltransmission-reception point (TRP) or to multiple physical TRPs that mayor may not be co-located. For example, where the term “base station”refers to a single physical TRP, the physical TRP may be an antenna ofthe base station corresponding to a cell of the base station. Where theterm “base station” refers to multiple co-located physical TRPs, thephysical TRPs may be an array of antennas (e.g., as in a multiple-inputmultiple-output (MIMO) system or where the base station employsbeamforming) of the base station. Where the term “base station” refersto multiple non-co-located physical TRPs, the physical TRPs may be adistributed antenna system (DAS) (a network of spatially separatedantennas connected to a common source via a transport medium) or aremote radio head (RRH) (a remote base station connected to a servingbase station). Alternatively, the non-co-located physical TRPs may bethe serving base station receiving the measurement report from the UEand a neighbor base station whose reference RF signals the UE ismeasuring. Because a TRP is the point from which a base stationtransmits and receives wireless signals, as used herein, references totransmission from or reception at a base station are to be understood asreferring to a particular TRP of the base station.

An “RF signal” comprises an electromagnetic wave of a given frequencythat transports information through the space between a transmitter anda receiver. As used herein, a transmitter may transmit a single “RFsignal” or multiple “RF signals” to a receiver. However, the receivermay receive multiple “RF signals” corresponding to each transmitted RFsignal due to the propagation characteristics of RF signals throughmultipath channels. The same transmitted RF signal on different pathsbetween the transmitter and receiver may be referred to as a “multipath”RF signal.

According to various aspects, FIG. 1 illustrates an exemplary wirelesscommunications system 100. The wireless communications system 100 (whichmay also be referred to as a wireless wide area network (WWAN)) mayinclude various base stations 102 and various UEs 104. The base stations102 may include macro cell base stations (high power cellular basestations) and/or small cell base stations (low power cellular basestations). In an aspect, the macro cell base station may include eNBswhere the wireless communications system 100 corresponds to an LTEnetwork, or gNBs where the wireless communications system 100corresponds to a NR network, or a combination of both, and the smallcell base stations may include femtocells, picocells, microcells, etc.

The base stations 102 may collectively form a RAN and interface with acore network 170 (e.g., an evolved packet core (EPC) or next generationcore (NGC)) through backhaul links 122, and through the core network 170to one or more location servers 172. In addition to other functions, thebase stations 102 may perform functions that relate to one or more oftransferring user data, radio channel ciphering and deciphering,integrity protection, header compression, mobility control functions(e.g., handover, dual connectivity), inter-cell interferencecoordination, connection setup and release, load balancing, distributionfor non-access stratum (NAS) messages, NAS node selection,synchronization, RAN sharing, multimedia broadcast multicast service(MBMS), subscriber and equipment trace, RAN information management(RIM), paging, positioning, and delivery of warning messages. The basestations 102 may communicate with each other directly or indirectly(e.g., through the EPC/NGC) over backhaul links 134, which may be wiredor wireless.

The base stations 102 may wirelessly communicate with the UEs 104. Eachof the base stations 102 may provide communication coverage for arespective geographic coverage area 110. In an aspect, one or more cellsmay be supported by a base station 102 in each geographic coverage area110. A “cell” is a logical communication entity used for communicationwith a base station (e.g., over some frequency resource, referred to asa carrier frequency, component carrier, carrier, band, or the like), andmay be associated with an identifier (e.g., a physical cell identifier(PCI), a virtual cell identifier (VCI)) for distinguishing cellsoperating via the same or a different carrier frequency. In some cases,different cells may be configured according to different protocol types(e.g., machine-type communication (MTC), narrowband IoT (NB-IoT),enhanced mobile broadband (eMBB), or others) that may provide access fordifferent types of UEs. Because a cell is supported by a specific basestation, the term “cell” may refer to either or both the logicalcommunication entity and the base station that supports it, depending onthe context. In some cases, the term “cell” may also refer to ageographic coverage area of a base station (e.g., a sector), insofar asa carrier frequency can be detected and used for communication withinsome portion of geographic coverage areas 110.

While neighboring macro cell base station 102 geographic coverage areas110 may partially overlap (e.g., in a handover region), some of thegeographic coverage areas 110 may be substantially overlapped by alarger geographic coverage area 110. For example, a small cell basestation 102′ may have a coverage area 110′ that substantially overlapswith the geographic coverage area 110 of one or more macro cell basestations 102. A network that includes both small cell and macro cellbase stations may be known as a heterogeneous network. A heterogeneousnetwork may also include home eNBs (HeNBs), which may provide service toa restricted group known as a closed subscriber group (CSG).

The communication links 120 between the base stations 102 and the UEs104 may include UL (also referred to as reverse link) transmissions froma UE 104 to a base station 102 and/or downlink (DL) (also referred to asforward link) transmissions from a base station 102 to a UE 104. Thecommunication links 120 may use MIMO antenna technology, includingspatial multiplexing, beamforming, and/or transmit diversity. Thecommunication links 120 may be through one or more carrier frequencies.Allocation of carriers may be asymmetric with respect to DL and UL(e.g., more or less carriers may be allocated for DL than for UL).

The wireless communications system 100 may further include a wirelesslocal area network (WLAN) access point (AP) 150 in communication withWLAN stations (STAs) 152 via communication links 154 in an unlicensedfrequency spectrum (e.g., 5 GHz). When communicating in an unlicensedfrequency spectrum, the WLAN STAs 152 and/or the WLAN AP 150 may performa clear channel assessment (CCA) or listen before talk (LBT) procedureprior to communicating in order to determine whether the channel isavailable.

The small cell base station 102′ may operate in a licensed and/or anunlicensed frequency spectrum. When operating in an unlicensed frequencyspectrum, the small cell base station 102′ may employ LTE or NRtechnology and use the same 5 GHz unlicensed frequency spectrum as usedby the WLAN AP 150. The small cell base station 102′, employing LTE/5Gin an unlicensed frequency spectrum, may boost coverage to and/orincrease capacity of the access network. NR in unlicensed spectrum maybe referred to as NR-U. LTE in an unlicensed spectrum may be referred toas LTE-U, licensed assisted access (LAA), or MulteFire.

The wireless communications system 100 may further include a millimeterwave (mmW) base station 180 that may operate in mmW frequencies and/ornear mmW frequencies in communication with a UE 182. Extremely highfrequency (EHF) is part of the RF in the electromagnetic spectrum. EHFhas a range of 30 GHz to 300 GHz and a wavelength between 1 millimeterand 10 millimeters. Radio waves in this band may be referred to as amillimeter wave. Near mmW may extend down to a frequency of 3 GHz with awavelength of 100 millimeters. The super high frequency (SHF) bandextends between 3 GHz and 30 GHz, also referred to as centimeter wave.Communications using the mmW/near mmW radio frequency band have highpath loss and a relatively short range. The mmW base station 180 and theUE 182 may utilize beamforming (transmit and/or receive) over a mmWcommunication link 184 to compensate for the extremely high path lossand short range. Further, it will be appreciated that in alternativeconfigurations, one or more base stations 102 may also transmit usingmmW or near mmW and beamforming. Accordingly, it will be appreciatedthat the foregoing illustrations are merely examples and should not beconstrued to limit the various aspects disclosed herein.

Transmit beamforming is a technique for focusing an RF signal in aspecific direction. Traditionally, when a network node (e.g., a basestation) broadcasts an RF signal, it broadcasts the signal in alldirections (omni-directionally). With transmit beamforming, the networknode determines where a given target device (e.g., a UE) is located(relative to the transmitting network node) and projects a strongerdownlink RF signal in that specific direction, thereby providing afaster (in terms of data rate) and stronger RF signal for the receivingdevice(s). To change the directionality of the RF signal whentransmitting, a network node can control the phase and relativeamplitude of the RF signal at each of the one or more transmitters thatare broadcasting the RF signal. For example, a network node may use anarray of antennas (referred to as a “phased array” or an “antennaarray”) that creates a beam of RF waves that can be “steered” to pointin different directions, without actually moving the antennas.Specifically, the RF current from the transmitter is fed to theindividual antennas with the correct phase relationship so that theradio waves from the separate antennas add together to increase theradiation in a desired direction, while canceling to suppress radiationin undesired directions.

Transmit beams may be quasi-collocated, meaning that they appear to thereceiver (e.g., a UE) as having the same parameters, regardless ofwhether or not the transmitting antennas of the network node themselvesare physically collocated. In NR, there are four types ofquasi-collocation (QCL) relations. Specifically, a QCL relation of agiven type means that certain parameters about a second reference RFsignal on a second beam can be derived from information about a sourcereference RF signal on a source beam. Thus, if the source reference RFsignal is QCL Type A, the receiver can use the source reference RFsignal to estimate the Doppler shift, Doppler spread, average delay, anddelay spread of a second reference RF signal transmitted on the samechannel. If the source reference RF signal is QCL Type B, the receivercan use the source reference RF signal to estimate the Doppler shift andDoppler spread of a second reference RF signal transmitted on the samechannel. If the source reference RF signal is QCL Type C, the receivercan use the source reference RF signal to estimate the Doppler shift andaverage delay of a second reference RF signal transmitted on the samechannel. If the source reference RF signal is QCL Type D, the receivercan use the source reference RF signal to estimate the spatial receiveparameter of a second reference RF signal transmitted on the samechannel.

In receive beamforming, the receiver uses a receive beam to amplify RFsignals detected on a given channel. For example, the receiver canincrease the gain setting and/or adjust the phase setting of an array ofantennas in a particular direction to amplify (e.g., to increase thegain level of) the RF signals received from that direction. Thus, when areceiver is said to beamform in a certain direction, it means the beamgain in that direction is high relative to the beam gain along otherdirections, or the beam gain in that direction is the highest comparedto the beam gain in that direction of all other receive beams availableto the receiver. This results in a stronger received signal strength(e.g., reference signal received power (RSRP), reference signal receivedquality (RSRQ), signal-to-interference-plus-noise ratio (SINR), etc.) ofthe RF signals received from that direction.

Receive beams may be spatially related. A spatial relation means thatparameters for a transmit beam for a second reference signal can bederived from information about a receive beam for a first referencesignal. For example, a UE may use a particular receive beam to receive areference downlink reference signal (e.g., synchronization signal block(SSB)) from a base station. The UE can then form a transmit beam forsending an uplink reference signal (e.g., sounding reference signal(SRS)) to that base station based on the parameters of the receive beam.

Note that a “downlink” beam may be either a transmit beam or a receivebeam, depending on the entity forming it. For example, if a base stationis forming the downlink beam to transmit a reference signal to a UE, thedownlink beam is a transmit beam. If the UE is forming the downlinkbeam, however, it is a receive beam to receive the downlink referencesignal. Similarly, an “uplink” beam may be either a transmit beam or areceive beam, depending on the entity forming it. For example, if a basestation is forming the uplink beam, it is an uplink receive beam, and ifa UE is forming the uplink beam, it is an uplink transmit beam.

In 5G, the frequency spectrum in which wireless nodes (e.g., basestations 102/180, UEs 104/182) operate is divided into multiplefrequency ranges, FR1 (from 450 to 6000 MHz), FR2 (from 24250 to 52600MHz), FR3 (above 52600 MHz), and FR4 (between FR1 and FR2). In amulti-carrier system, such as 5G, one of the carrier frequencies isreferred to as the “primary carrier” or “anchor carrier” or “primaryserving cell” or “PCell,” and the remaining carrier frequencies arereferred to as “secondary carriers” or “secondary serving cells” or“SCells.” In carrier aggregation, the anchor carrier is the carrieroperating on the primary frequency (e.g., FR1) utilized by a UE 104/182and the cell in which the UE 104/182 either performs the initial radioresource control (RRC) connection establishment procedure or initiatesthe RRC connection re-establishment procedure. The primary carriercarries all common and UE-specific control channels, and may be acarrier in a licensed frequency (however, this is not always the case).A secondary carrier is a carrier operating on a second frequency (e.g.,FR2) that may be configured once the RRC connection is establishedbetween the UE 104 and the anchor carrier and that may be used toprovide additional radio resources. In some cases, the secondary carriermay be a carrier in an unlicensed frequency. The secondary carrier maycontain only necessary signaling information and signals, for example,those that are UE-specific may not be present in the secondary carrier,since both primary uplink and downlink carriers are typicallyUE-specific. This means that different UEs 104/182 in a cell may havedifferent downlink primary carriers. The same is true for the uplinkprimary carriers. The network is able to change the primary carrier ofany UE 104/182 at any time. This is done, for example, to balance theload on different carriers. Because a “serving cell” (whether a PCell oran SCell) corresponds to a carrier frequency/component carrier overwhich some base station is communicating, the term “cell,” “servingcell,” “component carrier,” “carrier frequency,” and the like can beused interchangeably.

For example, still referring to FIG. 1, one of the frequencies utilizedby the macro cell base stations 102 may be an anchor carrier (or“PCell”) and other frequencies utilized by the macro cell base stations102 and/or the mmW base station 180 may be secondary carriers(“SCells”). The simultaneous transmission and/or reception of multiplecarriers enables the UE 104/182 to significantly increase its datatransmission and/or reception rates. For example, two 20 MHz aggregatedcarriers in a multi-carrier system would theoretically lead to atwo-fold increase in data rate (i.e., 40 MHz), compared to that attainedby a single 20 MHz carrier.

The wireless communications system 100 may further include one or moreUEs, such as UE 190, that connects indirectly to one or morecommunication networks via one or more device-to-device (D2D)peer-to-peer (P2P) links. In the example of FIG. 1, UE 190 has a D2D P2Plink 192 with one of the UEs 104 connected to one of the base stations102 (e.g., through which UE 190 may indirectly obtain cellularconnectivity) and a D2D P2P link 194 with WLAN STA 152 connected to theWLAN AP 150 (through which UE 190 may indirectly obtain WLAN-basedInternet connectivity). In an example, the D2D P2P links 192 and 194 maybe supported with any well-known D2D RAT, such as LTE Direct (LTE-D),WiFi Direct (WiFi-D), Bluetooth®, and so on.

The wireless communications system 100 may further include a UE 164 thatmay communicate with a macro cell base station 102 over a communicationlink 120 and/or the mmW base station 180 over a mmW communication link184. For example, the macro cell base station 102 may support a PCelland one or more SCells for the UE 164 and the mmW base station 180 maysupport one or more SCells for the UE 164.

According to various aspects, FIG. 2A illustrates an example wirelessnetwork structure 200. For example, an NGC 210 (also referred to as a“5GC”) can be viewed functionally as control plane functions 214 (e.g.,UE registration, authentication, network access, gateway selection,etc.) and user plane functions 212, (e.g., UE gateway function, accessto data networks, IP routing, etc.) which operate cooperatively to formthe core network. User plane interface (NG-U) 213 and control planeinterface (NG-C) 215 connect the gNB 222 to the NGC 210 and specificallyto the control plane functions 214 and user plane functions 212. In anadditional configuration, an eNB 224 may also be connected to the NGC210 via NG-C 215 to the control plane functions 214 and NG-U 213 to userplane functions 212. Further, eNB 224 may directly communicate with gNB222 via a backhaul connection 223. In some configurations, the New RAN220 may only have one or more gNBs 222, while other configurationsinclude one or more of both eNBs 224 and gNBs 222. Either gNB 222 or eNB224 may communicate with UEs 204 (e.g., any of the UEs depicted in FIG.1). Another optional aspect may include location server 230, which maybe in communication with the NGC 210 to provide location assistance forUEs 204. In an aspect, the location server 230 may be an evolved servingmobile location center (E-SMLC), a secure user plane location (SUPL)location platform (SLP), a gateway mobile location center (GMLC), alocation management function (LMF), or the like. The location server 230can be implemented as a plurality of separate servers (e.g., physicallyseparate servers, different software modules on a single server,different software modules spread across multiple physical servers,etc.), or alternately may each correspond to a single server. Thelocation server 230 can be configured to support one or more locationservices for UEs 204 that can connect to the location server 230 via thecore network, NGC 210, and/or via the Internet (not illustrated).Further, the location server 230 may be integrated into a component ofthe core network, or alternatively may be external to the core network.

According to various aspects, FIG. 2B illustrates another examplewireless network structure 250. For example, an NGC 260 (also referredto as a “5GC”) can be viewed functionally as control plane functions,provided by an access and mobility management function (AMF)/user planefunction (UPF) 264, and user plane functions, provided by a sessionmanagement function (SMF) 262, which operate cooperatively to form thecore network (i.e., NGC 260). User plane interface 263 and control planeinterface 265 connect the eNB 224 to the NGC 260 and specifically to SMF262 and AMF/UPF 264, respectively. In an additional configuration, a gNB222 may also be connected to the NGC 260 via control plane interface 265to AMF/UPF 264 and user plane interface 263 to SMF 262. Further, eNB 224may directly communicate with gNB 222 via the backhaul connection 223,with or without gNB direct connectivity to the NGC 260. In someconfigurations, the New RAN 220 may only have one or more gNBs 222,while other configurations include one or more of both eNBs 224 and gNBs222. Either gNB 222 or eNB 224 may communicate with UEs 204 (e.g., anyof the UEs depicted in FIG. 1). The base stations of the New RAN 220communicate with the AMF-side of the AMF/UPF 264 over the N2 interfaceand the UPF-side of the AMF/UPF 264 over the N3 interface.

The functions of the AMF include registration management, connectionmanagement, reachability management, mobility management, lawfulinterception, transport for session management (SM) messages between theUE 204 and the SMF 262, transparent proxy services for routing SMmessages, access authentication and access authorization, transport forshort message service (SMS) messages between the UE 204 and the shortmessage service function (SMSF) (not shown), and security anchorfunctionality (SEAF). The AMF also interacts with the authenticationserver function (AUSF) (not shown) and the UE 204, and receives theintermediate key that was established as a result of the UE 204authentication process. In the case of authentication based on a UMTS(universal mobile telecommunications system) subscriber identity module(USIM), the AMF retrieves the security material from the AUSF. Thefunctions of the AMF also include security context management (SCM). TheSCM receives a key from the SEAF that it uses to derive access-networkspecific keys. The functionality of the AMF also includes locationservices management for regulatory services, transport for locationservices messages between the UE 204 and the LMF 270, as well as betweenthe New RAN 220 and the LMF 270, evolved packet system (EPS) beareridentifier allocation for interworking with the EPS, and UE 204 mobilityevent notification. In addition, the AMF also supports functionalitiesfor non-3GPP access networks.

Functions of the UPF include acting as an anchor point forintra-/inter-RAT mobility (when applicable), acting as an externalprotocol data unit (PDU) session point of interconnect to the datanetwork (not shown), providing packet routing and forwarding, packetinspection, user plane policy rule enforcement (e.g., gating,redirection, traffic steering), lawful interception (user planecollection), traffic usage reporting, quality of service (QoS) handlingfor the user plane (e.g., UL/DL rate enforcement, reflective QoS markingin the DL), UL traffic verification (service data flow (SDF) to QoS flowmapping), transport level packet marking in the UL and DL, DL packetbuffering and DL data notification triggering, and sending andforwarding of one or more “end markers” to the source RAN node.

The functions of the SMF 262 include session management, UE Internetprotocol (IP) address allocation and management, selection and controlof user plane functions, configuration of traffic steering at the UPF toroute traffic to the proper destination, control of part of policyenforcement and QoS, and downlink data notification. The interface overwhich the SMF 262 communicates with the AMF-side of the AMF/UPF 264 isreferred to as the N11 interface.

Another optional aspect may include a LMF 270, which may be incommunication with the NGC 260 to provide location assistance for UEs204. The LMF 270 can be implemented as a plurality of separate servers(e.g., physically separate servers, different software modules on asingle server, different software modules spread across multiplephysical servers, etc.), or alternately may each correspond to a singleserver. The LMF 270 can be configured to support one or more locationservices for UEs 204 that can connect to the LMF 270 via the corenetwork, NGC 260, and/or via the Internet (not illustrated).

FIGS. 3A, 3B, and 3C illustrate several sample components (representedby corresponding blocks) that may be incorporated into a UE 302 (whichmay correspond to any of the UEs described herein), a base station 304(which may correspond to any of the base stations described herein), anda network entity 306 (which may correspond to or embody any of thenetwork functions described herein, including the location server 230and the LMF 270) to support the file transmission operations as taughtherein. It will be appreciated that these components may be implementedin different types of apparatuses in different implementations (e.g., inan ASIC, in a system-on-chip (SoC), etc.). The illustrated componentsmay also be incorporated into other apparatuses in a communicationsystem. For example, other apparatuses in a system may includecomponents similar to those described to provide similar functionality.Also, a given apparatus may contain one or more of the components. Forexample, an apparatus may include multiple transceiver components thatenable the apparatus to operate on multiple carriers and/or communicatevia different technologies.

The UE 302 and the base station 304 each include wireless wide areanetwork (WWAN) transceiver 310 and 350, respectively, configured tocommunicate via one or more wireless communication networks (not shown),such as an NR network, an LTE network, a GSM network, and/or the like.The WWAN transceivers 310 and 350 may be connected to one or moreantennas 316 and 356, respectively, for communicating with other networknodes, such as other UEs, access points, base stations (e.g., eNBs,gNBs), etc., via at least one designated RAT (e.g., NR, LTE, GSM, etc.)over a wireless communication medium of interest (e.g., some set oftime/frequency resources in a particular frequency spectrum). The WWANtransceivers 310 and 350 may be variously configured for transmittingand encoding signals 318 and 358 (e.g., messages, indications,information, and so on), respectively, and, conversely, for receivingand decoding signals 318 and 358 (e.g., messages, indications,information, pilots, and so on), respectively, in accordance with thedesignated RAT. Specifically, the transceivers 310 and 350 include oneor more transmitters 314 and 354, respectively, for transmitting andencoding signals 318 and 358, respectively, and one or more receivers312 and 352, respectively, for receiving and decoding signals 318 and358, respectively.

The UE 302 and the base station 304 also include, at least in somecases, wireless local area network (WLAN) transceivers 320 and 360,respectively. The WLAN transceivers 320 and 360 may be connected to oneor more antennas 326 and 366, respectively, for communicating with othernetwork nodes, such as other UEs, access points, base stations, etc.,via at least one designated RAT (e.g., WiFi, LTE-D, Bluetooth®, etc.)over a wireless communication medium of interest. The WLAN transceivers320 and 360 may be variously configured for transmitting and encodingsignals 328 and 368 (e.g., messages, indications, information, and soon), respectively, and, conversely, for receiving and decoding signals328 and 368 (e.g., messages, indications, information, pilots, and soon), respectively, in accordance with the designated RAT. Specifically,the transceivers 320 and 360 include one or more transmitters 324 and364, respectively, for transmitting and encoding signals 328 and 368,respectively, and one or more receivers 322 and 362, respectively, forreceiving and decoding signals 328 and 368, respectively.

Transceiver circuitry including a transmitter and a receiver maycomprise an integrated device (e.g., embodied as a transmitter circuitand a receiver circuit of a single communication device) in someimplementations, may comprise a separate transmitter device and aseparate receiver device in some implementations, or may be embodied inother ways in other implementations. In an aspect, a transmitter mayinclude or be coupled to a plurality of antennas (e.g., antennas 316,336, and 376), such as an antenna array, that permits the respectiveapparatus to perform transmit “beamforming,” as described herein.Similarly, a receiver may include or be coupled to a plurality ofantennas (e.g., antennas 316, 336, and 376), such as an antenna array,that permits the respective apparatus to perform receive beamforming, asdescribed herein. In an aspect, the transmitter and receiver may sharethe same plurality of antennas (e.g., antennas 316, 336, and 376), suchthat the respective apparatus can only receive or transmit at a giventime, not both at the same time. A wireless communication device (e.g.,one or both of the transceivers 310 and 320 and/or 350 and 360) of theapparatuses 302 and/or 304 may also comprise a network listen module(NLM) or the like for performing various measurements.

The apparatuses 302 and 304 also include, at least in some cases,satellite positioning systems (SPS) receivers 330 and 370. The SPSreceivers 330 and 370 may be connected to one or more antennas 336 and376, respectively, for receiving SPS signals 338 and 378, respectively,such as global positioning system (GPS) signals, global navigationsatellite system (GLONASS) signals, Galileo signals, Beidou signals,Indian Regional Navigation Satellite System (NAVIC), Quasi-ZenithSatellite System (QZSS), etc. The SPS receivers 330 and 370 may compriseany suitable hardware and/or software for receiving and processing SPSsignals 338 and 378, respectively. The SPS receivers 330 and 370 requestinformation and operations as appropriate from the other systems, andperforms calculations necessary to determine the apparatus' 302 and 304positions using measurements obtained by any suitable SPS algorithm.

The base station 304 and the network entity 306 each include at leastone network interfaces 380 and 390 for communicating with other networkentities. For example, the network interfaces 380 and 390 (e.g., one ormore network access ports) may be configured to communicate with one ormore network entities via a wire-based or wireless backhaul connection.In some aspects, the network interfaces 380 and 390 may be implementedas transceivers configured to support wire-based or wireless signalcommunication. This communication may involve, for example, sending andreceiving: messages, parameters, or other types of information.

The apparatuses 302, 304, and 306 also include other components that maybe used in conjunction with the operations as disclosed herein. The UE302 includes processor circuitry implementing a processing system 332for providing functionality relating to, for example, false base station(FBS) detection as disclosed herein and for providing other processingfunctionality. The base station 304 includes a processing system 384 forproviding functionality relating to, for example, FBS detection asdisclosed herein and for providing other processing functionality. Thenetwork entity 306 includes a processing system 394 for providingfunctionality relating to, for example, FBS detection as disclosedherein and for providing other processing functionality. In an aspect,the processing systems 332, 384, and 394 may include, for example, oneor more general purpose processors, multi-core processors, ASICs,digital signal processors (DSPs), field programmable gate arrays (FPGA),or other programmable logic devices or processing circuitry.

The apparatuses 302, 304, and 306 include memory circuitry implementingmemory components 340, 386, and 396 (e.g., each including a memorydevice), respectively, for maintaining information (e.g., informationindicative of reserved resources, thresholds, parameters, and so on). Insome cases, the apparatuses 302, 304, and 306 may include assistancedata modules 342, 388, and 398, respectively. The assistance datamodules 342, 388, and 398 may be hardware circuits that are part of orcoupled to the processing systems 332, 384, and 394, respectively, that,when executed, cause the apparatuses 302, 304, and 306 to perform thefunctionality described herein. In other aspects, the assistance datamodules 342, 388, and 398 may be external to the processing systems 332,384, and 394 (e.g., part of a modem processing system, integrated withanother processing system, etc.). Alternatively, the assistance datamodules 342, 388, and 398 may be memory modules (as shown in FIGS. 3A-C)stored in the memory components 340, 386, and 396, respectively, that,when executed by the processing systems 332, 384, and 394 (or a modemprocessing system, another processing system, etc.), cause theapparatuses 302, 304, and 306 to perform the functionality describedherein.

The UE 302 may include one or more sensors 344 coupled to the processingsystem 332 to provide movement and/or orientation information that isindependent of motion data derived from signals received by the WWANtransceiver 310, the WLAN transceiver 320, and/or the SPS receiver 330.By way of example, the sensor(s) 344 may include an accelerometer (e.g.,a micro-electrical mechanical systems (MEMS) device), a gyroscope, ageomagnetic sensor (e.g., a compass), an altimeter (e.g., a barometricpressure altimeter), and/or any other type of movement detection sensor.Moreover, the sensor(s) 344 may include a plurality of different typesof devices and combine their outputs in order to provide motioninformation. For example, the sensor(s) 344 may use a combination of amulti-axis accelerometer and orientation sensors to provide the abilityto compute positions in 2D and/or 3D coordinate systems.

In addition, the UE 302 includes a user interface 346 for providingindications (e.g., audible and/or visual indications) to a user and/orfor receiving user input (e.g., upon user actuation of a sensing devicesuch a keypad, a touch screen, a microphone, and so on). Although notshown, the apparatuses 304 and 306 may also include user interfaces.

Referring to the processing system 384 in more detail, in the downlink,IP packets from the network entity 306 may be provided to the processingsystem 384. The processing system 384 may implement functionality for anRRC layer, a packet data convergence protocol (PDCP) layer, a radio linkcontrol (RLC) layer, and a medium access control (MAC) layer. Theprocessing system 384 may provide RRC layer functionality associatedwith broadcasting of system information (e.g., master information block(MIB), system information blocks (SIGs)), RRC connection control (e.g.,RRC connection paging, RRC connection establishment, RRC connectionmodification, and RRC connection release), inter-RAT mobility, andmeasurement configuration for UE measurement reporting; PDCP layerfunctionality associated with header compression/decompression, security(ciphering, deciphering, integrity protection, integrity verification),and handover support functions; RLC layer functionality associated withthe transfer of upper layer packet data units (PDUs), error correctionthrough ARQ, concatenation, segmentation, and reassembly of RLC servicedata units (SDUs), re-segmentation of RLC data PDUs, and reordering ofRLC data PDUs; and MAC layer functionality associated with mappingbetween logical channels and transport channels, scheduling informationreporting, error correction, priority handling, and logical channelprioritization.

The transmitter 354 and the receiver 352 may implement Layer-1functionality associated with various signal processing functions.Layer-1, which includes a physical (PHY) layer, may include errordetection on the transport channels, forward error correction (FEC)coding/decoding of the transport channels, interleaving, rate matching,mapping onto physical channels, modulation/demodulation of physicalchannels, and MIMO antenna processing. The transmitter 354 handlesmapping to signal constellations based on various modulation schemes(e.g., binary phase-shift keying (BPSK), quadrature phase-shift keying(QPSK), M-phase-shift keying (M-PSK), M-quadrature amplitude modulation(M-QAM)). The coded and modulated symbols may then be split intoparallel streams. Each stream may then be mapped to an orthogonalfrequency division multiplexing (OFDM) subcarrier, multiplexed with areference signal (e.g., pilot) in the time and/or frequency domain, andthen combined together using an Inverse Fast Fourier Transform (IFFT) toproduce a physical channel carrying a time domain OFDM symbol stream.The OFDM stream is spatially precoded to produce multiple spatialstreams. Channel estimates from a channel estimator may be used todetermine the coding and modulation scheme, as well as for spatialprocessing. The channel estimate may be derived from a reference signaland/or channel condition feedback transmitted by the UE 302. Eachspatial stream may then be provided to one or more different antennas356. The transmitter 354 may modulate an RF carrier with a respectivespatial stream for transmission.

At the UE 302, the receiver 312 receives a signal through its respectiveantenna(s) 316. The receiver 312 recovers information modulated onto anRF carrier and provides the information to the processing system 332.The transmitter 314 and the receiver 312 implement Layer-1 functionalityassociated with various signal processing functions. The receiver 312may perform spatial processing on the information to recover any spatialstreams destined for the UE 302. If multiple spatial streams aredestined for the UE 302, they may be combined by the receiver 312 into asingle OFDM symbol stream. The receiver 312 then converts the OFDMsymbol stream from the time-domain to the frequency domain using a fastFourier transform (FFT). The frequency domain signal comprises aseparate OFDM symbol stream for each subcarrier of the OFDM signal. Thesymbols on each subcarrier, and the reference signal, are recovered anddemodulated by determining the most likely signal constellation pointstransmitted by the base station 304. These soft decisions may be basedon channel estimates computed by a channel estimator. The soft decisionsare then decoded and de-interleaved to recover the data and controlsignals that were originally transmitted by the base station 304 on thephysical channel. The data and control signals are then provided to theprocessing system 332, which implements Layer-3 and Layer-2functionality.

In the UL, the processing system 332 provides demultiplexing betweentransport and logical channels, packet reassembly, deciphering, headerdecompression, and control signal processing to recover IP packets fromthe core network. The processing system 332 is also responsible forerror detection.

Similar to the functionality described in connection with the DLtransmission by the base station 304, the processing system 332 providesRRC layer functionality associated with system information (e.g., MIB,SIBs) acquisition, RRC connections, and measurement reporting; PDCPlayer functionality associated with header compression/decompression,and security (ciphering, deciphering, integrity protection, integrityverification); RLC layer functionality associated with the transfer ofupper layer PDUs, error correction through ARQ, concatenation,segmentation, and reassembly of RLC SDUs, re-segmentation of RLC dataPDUs, and reordering of RLC data PDUs; and MAC layer functionalityassociated with mapping between logical channels and transport channels,multiplexing of MAC SDUs onto transport blocks (TBs), demultiplexing ofMAC SDUs from TBs, scheduling information reporting, error correctionthrough HARQ, priority handling, and logical channel prioritization.

Channel estimates derived by the channel estimator from a referencesignal or feedback transmitted by the base station 304 may be used bythe transmitter 314 to select the appropriate coding and modulationschemes, and to facilitate spatial processing. The spatial streamsgenerated by the transmitter 314 may be provided to different antenna(s)316. The transmitter 314 may modulate an RF carrier with a respectivespatial stream for transmission.

The UL transmission is processed at the base station 304 in a mannersimilar to that described in connection with the receiver function atthe UE 302. The receiver 352 receives a signal through its respectiveantenna(s) 356. The receiver 352 recovers information modulated onto anRF carrier and provides the information to the processing system 384.

In the UL, the processing system 384 provides demultiplexing betweentransport and logical channels, packet reassembly, deciphering, headerdecompression, control signal processing to recover IP packets from theUE 302. IP packets from the processing system 384 may be provided to thecore network. The processing system 384 is also responsible for errordetection.

For convenience, the apparatuses 302, 304, and/or 306 are shown in FIGS.3A-C as including various components that may be configured according tothe various examples described herein. It will be appreciated, however,that the illustrated blocks may have different functionality indifferent designs.

The various components of the apparatuses 302, 304, and 306 maycommunicate with each other over data buses 334, 382, and 392,respectively. The components of FIGS. 3A-C may be implemented in variousways. In some implementations, the components of FIGS. 3A-C may beimplemented in one or more circuits such as, for example, one or moreprocessors and/or one or more ASICs (which may include one or moreprocessors). Here, each circuit may use and/or incorporate at least onememory component for storing information or executable code used by thecircuit to provide this functionality. For example, some or all of thefunctionality represented by blocks 310 to 346 may be implemented byprocessor and memory component(s) of the UE 302 (e.g., by execution ofappropriate code and/or by appropriate configuration of processorcomponents). Similarly, some or all of the functionality represented byblocks 350 to 388 may be implemented by processor and memorycomponent(s) of the base station 304 (e.g., by execution of appropriatecode and/or by appropriate configuration of processor components). Also,some or all of the functionality represented by blocks 390 to 398 may beimplemented by processor and memory component(s) of the network entity306 (e.g., by execution of appropriate code and/or by appropriateconfiguration of processor components). For simplicity, variousoperations, acts, and/or functions are described herein as beingperformed “by a UE,” “by a base station,” “by a positioning entity,”etc. However, as will be appreciated, such operations, acts, and/orfunctions may actually be performed by specific components orcombinations of components of the UE, base station, positioning entity,etc., such as the processing systems 332, 384, 394, the transceivers310, 320, 350, and 360, the memory components 340, 386, and 396, theassistance data modules 342, 388, and 398, etc.

A position estimate (e.g., for any of the UEs described herein) may bereferred to by other names, such as a location estimate, location,position, position fix, fix, or the like. A position estimate may begeodetic and comprise coordinates (e.g., latitude, longitude, andpossibly altitude) or may be civic and comprise a street address, postaladdress, or some other verbal description of a location. A positionestimate may further be defined relative to some other known location ordefined in absolute terms (e.g., using latitude, longitude, and possiblyaltitude). A position estimate may include an expected error oruncertainty (e.g., by including an area or volume within which thelocation is expected to be included with some specified or default levelof confidence).

In LTE, in order to support determining the location of a UE, a locationserver (e.g., an E-SMLC, SLP, GMLC, etc.) may support one or morepositioning protocols, such as LPP defined by 3GPP. A positioningprotocol may be used between a UE and a location server to coordinateand control position determination for a UE. The positioning protocolmay define: (a) positioning related procedures that may be executed bythe location server and/or the UE; and/or (b) communication or signalingexchanged between the UE and the location server related to positioningof the UE. For control plane location, the location server(specifically, an E-SMLC) may use a positioning protocol, such as theLPP type A protocol (LPPa) defined by 3GPP, to obtain location relatedinformation for a UE from elements in the RAN (e.g., New RAN 220), suchas any of eNBs 224. The location related information that is obtainedmay include location related measurements for the UE or otherinformation to assist location of the UE, such as information onpositioning reference signaling (PRS) signals transmitted by one or moreof eNBs or location coordinates of one or more of eNBs. LPP is known inthe art and described in various publicly available technicalspecifications (TSs) from 3GPP (e.g., 3GPP TS 36.355).

FIG. 4 illustrates a conventional LPP call flow between a UE 204 and alocation server 230 for performing positioning operations. Asillustrated in FIG. 4, positioning of the UE 204 is supported via anexchange of LPP messages between the UE 204 and the location server 230(e.g., an E-SMLC or SLP). The LPP messages may be exchanged between UE204 and the location server 230 via an eNB 224 and a core network (e.g.,via a mobility management entity (MME) with a control plane locationsolution when location server 230 comprises an E-SMLC or via packet datanetwork gateway/serving gateway (P/SGW) with a user plane locationsolution when location server 230 comprises an SLP). For simplicity,only the eNB 224 is shown in FIG. 4. The procedure shown in FIG. 4 maybe used to position the UE 204 in order to support variouslocation-related services, such as navigation for UE 204 (or for theuser of UE 204), or for routing, or for provision of an accuratelocation to a public safety answering point (PSAP) in association withan emergency call from UE 204 to a PSAP, or for some other reason.

Initially, the UE 204 may receive a request for its positioningcapabilities from the location server 230 at stage 402 (e.g., an LPPRequest Capabilities message). At stage 404, the UE 204 provides itspositioning capabilities to the location server 230 relative to the LPPprotocol by sending an LPP Provide Capabilities message to locationserver 230 indicating the position methods and features of theseposition methods that are supported by the UE 204 using LPP. Thecapabilities indicated in the LPP Provide Capabilities message may, insome aspects, indicate that the UE 204 supports OTDOA positioning andmay indicate the capabilities of the UE 204 to support OTDOA. If OTDOAcapabilities were requested in stage 402, this message includesinformation elements such as the OTDOA mode supported (note: LPPsupports only a UE-assisted mode), supported frequency bands, andsupport for inter-frequency RSTD measurements.

Upon reception of the LPP Provide Capabilities message, the locationserver 230 determines to use the OTDOA position method based on theindicated UE 204 support for OTDOA at stage 404 and determines areference cell and neighbor cells (or a reference cell set and/orneighbor cell sets) for OTDOA. At stage 406, the location server 230then sends an LPP Provide Assistance Data message to the UE 204. TheOTDOA assistance data includes assistance for the reference cell and upto 72 neighbor cells. If the UE 204 indicated support forinter-frequency RSTD measurements, the neighbor cell assistance data maybe provided for up to three frequency layers.

In some implementations, the LPP Provide Assistance Data message atstage 406 may be sent by the location server 230 to the UE 204 inresponse to an LPP Request Assistance Data message sent by the UE 204 tothe location server 230 (not shown in FIG. 4). An LPP Request AssistanceData message may include an identifier of the UE's 204 serving cell anda request for the PRS configuration of neighboring cells.

The LPP Provide Assistance Data message may include positioningassistance data in the form of OTDOA assistance data to enable or tohelp enable the UE 204 to obtain and return OTDOA RSTD measurements, andmay include information for the reference cell (or reference cell set)identified at stage 406 (e.g., corresponding to one of eNBs 224). Theinformation for the reference cell (or reference cell set) may include aglobal ID for the reference cell (or a global ID for each cell in areference cell set), a physical cell ID for the reference cell (or aphysical cell ID for each cell in reference cell set), carrier frequencyinformation, and PRS configuration parameters for the reference cell (orreference cell set).

The LPP Provide Assistance Data message may also include OTDOAassistance data for neighbor cells (and/or neighbor cell sets)identified at stage 406 (e.g., corresponding to other eNBs 224). Theinformation provided for each neighbor cell (and/or each neighbor cellset) in the LPP Provide Assistance Data message may be similar to thatprovided for the reference cell (e.g., may include a cell ID, cellfrequency, and PRS configuration parameters) and may further include,for example, a slot number and/or subframe offset between the neighborcell (or neighbor cell set) and the reference cell (or reference cellset), and/or an expected approximate RSTD value and RSTD uncertainty.

At stage 408, the location server 230 sends a request for locationinformation to the UE 204. The request may be an LPP Request LocationInformation message. This message usually includes information elementssuch as location information type, desired accuracy of the locationestimate, and response time. Note that in some implementations, the LPPProvide Assistance Data message sent at stage 406 may be sent after theLPP Request Location Information message at 408 if, for example, the UE204 sends a request for assistance data to location server 230 (e.g., inan LPP Request Assistance Data message, not shown in FIG. 4) afterreceiving the request for location information at stage 408. The requestfor location information sent at stage 408 may request the UE 204 toobtain RSTD measurements for OTDOA in, for example, association with theinformation for the reference cell (or reference cell set) and neighborcells (and/or neighbor cell sets) sent to UE 204 at stage 406.

At stage 410, the UE 204 utilizes the OTDOA positioning assistanceinformation received at stage 406 and any additional data (e.g., adesired location accuracy or a maximum response time) received at stage408 to perform RSTD measurements for the OTDOA positioning method. TheRSTD measurements may be made between the reference cell (set) indicatedat stage 406, or a reference cell (or reference cell set) determined bythe UE 204 from the neighbor cells (and/or neighbor cell sets) indicatedat stage 406, and one or more of the (other) neighbor cells (and/orneighbor cell sets) indicated at stage 406. The UE 204 utilizes the PRSconfiguration parameters for the reference and neighbor cells (and/orcell sets) provided at stage 406 to acquire and measure PRS signals forthese cells (and/or cell sets) in order to obtain RSTD measurements.

At stage 412, the UE 204 may send an LPP Provide Location Informationmessage to the location server 230 conveying the RSTD measurements thatwere obtained at stage 410 and before or when any maximum response timehas expired (e.g., a maximum response time provided by the locationserver 230 at stage 408). The LPP Provide Location Information messageat stage 412 may include the time (or times) at which the RSTDmeasurements were obtained and the identity of the reference cell (or anidentity of one cell in a reference cell set) for the RSTD measurements(e.g., the reference cell ID and carrier frequency). The message atstage 412 may also include a neighbor cell measurement list including,for each measured neighbor cell (and/or for each measured neighbor cellset), the identity of the cell or of one cell in a cell set (e.g., thephysical cell ID, global cell ID, and/or cell carrier frequency), theRSTD measurement for the cell (or cell set), and the quality of the RSTDmeasurement for the cell (or cell set) (e.g., the expected error in theRSTD measurements). The neighbor cell measurement list may include RSTDdata for one or more cells. Note that the time between the request forlocation information at 408 and the response at 412 is the “responsetime.”

The location server 230 computes an estimated location of the UE 204using OTDOA positioning techniques based, at least in part, onmeasurements received in the LPP Provide Location Information message atstage 412 (e.g., RSTD measurements).

In LTE, the entity requesting a position fix is generally the UE 204(e.g., a location service running on the UE 204) or an emergency callcenter (e.g., a PSAP), and the positioning entity is generally thelocation server 230 (e.g., an E-SMLC). In contrast, with NR, therequester of the position fix and the engine computing the position fixmay be at other locations as compared to LTE. More specifically, whilethe requester in NR may still be the UE 204 and the positioning entitymay still be the location server 230, there are other possibilities. Forexample, the positioning entity (e.g., an LMF) may be located at a gNB222 or in the UE 204 itself, rather than on a remote server. As anotherexample, the requester may be a gNB 222, such as in factory automation,vehicle-to-everything (V2X), augmented reality (AR), and virtual reality(VR) use-cases, as opposed to the UE in LTE. As such, there is a needfor more flexibility in the assistance data formats and procedures in NRto handle these different use cases.

Accordingly, the present disclosure provides various positioningassistance data procedures for NR. In an aspect, a UE 204 can requestinformation for specific gNBs 222 or other TRPs.

FIGS. 5A and 5B illustrate exemplary call flows between a UE 204 and anLMF 270 for performing positioning operations, according to aspects ofthe disclosure. At 502, the UE 204 sends a Request Assistance Datamessage to the LMF 270 via the serving cell/serving gNB 222. In LTE, aUE 204 can indicate (identify) its current serving cell when requestingPRS configuration in an LPP Request Assistance Data message. In thepresent disclosure, if the UE 204 is connected to an NR network (as inthe example of FIG. 5A), in addition to identifying the current servingcell, the Request Assistance Data message can also indicate (identify)neighbor cells and/or neighbor TRPs of the UE 204 and their signalstrengths, which could be measured on the synchronization signal block(SSB), or channel state information reference signal (CSI-RS), or PRS ifconfigured.

The disclosed Request Assistance Data message transmitted/received at502 may also include a request for PRS (or other positioning referencesignaling) from particular neighbor cells and/or TRPs, and/or a requestfor base station almanac (BSA) information on particular neighbor cellsand/or TRPs. The base station almanac information for a given neighborcell/TRP may include the geographic location of the antennas/antennaarrays of the corresponding gNB/TRP, the orientation, tilt, and heightof the antennas/antenna arrays, and/or the antenna/antenna array andbeam patterns. The base station almanac information may also include theextent to which the neighbor cell/TRP is synchronized with the servingcell (to assist with OTDOA and/or uplink time difference of arrival(UTDOA)), and/or the extent to which the neighbor cell/TRP group-delayis calibrated (to assist with multi-RTT).

At 504, the LMF 270 can reply with a Provide Assistance Data messagecontaining the requested information for the identified cells/TRPs. Thecells/TRPs may be identified by an identifier or by an index valuecorresponding to their position in the Request Assistance Data messagetransmitted/received at 502. For example, the cells/TRPs may beidentified by their PCI, enhanced cell identifier (E-CID), VCI, etc., orsimply some identifier known to the LMF 270 and the UE 204. In additionto the request information, the LMF 270 can instruct the neighboringcells/TRPs to transmit positioning reference signals (e.g., PRS) to theUE 204 according to the configuration sent to the UE 204 in the ProvideAssistance Data message.

In an aspect, the Request Assistance Data message may be sent to the LMF270 via the serving gNB 222, as illustrated in FIG. 5A. However, wherethe LMF 270 is part of the serving gNB 222, the Request Assistance Datamessage may be sent directly to the serving gNB 222, as illustrated inFIG. 5B at stage 512, and processed by the LMF 270 at the serving gNB222. In that case, the serving gNB 222 sends the Provide Assistance Datamessage containing the requested information for the identified cells at514.

Alternatively, where the LMF 270 is not part of the serving gNB 222,rather than simply forward the Request Assistance Data message receivedat 512 to the LMF 270, as in FIG. 5A, the serving gNB 222 may decode theRequest Assistance Data message and forward it to the LMF 270 (e.g., viathe NR Positioning Protocol type A (NRPPa)) at 522. The serving gNB 222would then receive the Provide Assistance Data message from the LMF 270at stage 524 and forward it to the UE 204 at stage 514. As is known inthe art, NRPPa specifies the control plane radio network layer signalingprocedures between a gNB 222 and the LMF 270. The NRPPa LocationInformation Transfer Procedures module contains procedures used tohandle the transfer of positioning related information between New RANnodes (e.g., gNBs 222) and the LMF 270. NRPPa is described in variouspublicly available technical specifications (TSs) from 3GPP (e.g., 3GPPTS 38.455). This approach allows the gNB 222 to combine RequestAssistance Data messages from multiple requesting UEs 204 into a singlemessage to the LMF 270, for example, eliminating duplicate requests ifmultiple UEs 204 have exactly the same request or request type. This canreduce traffic in the core network, which may be especially important inscenarios such as factory automation with large number of UEs 204needing positioning.

In an aspect, the call flows illustrated in FIGS. 5A and 5B may replacethe LPP Provide Assistance Data stage at 406 of FIG. 4. Thus, althoughnot shown in FIGS. 5A and 5B, the illustrated positioning method maybegin with an exchange of capability messages between the UE 204 and theLMF 270, similar to stages 402 and 404 of FIG. 4, and may continue withthe LMF 270 sending a Request Location Information message to the UE 204and the UE 204 responding with a Provide Location Information message,as described above with reference to stages 408 to 412 of FIG. 4, butusing the new information exchanged at 502 and 504 or 512 and 514.

Note that the terms “positioning reference signal” and “PRS” maysometimes refer to specific reference signals that are used forpositioning in LTE systems. However, as used herein, unless otherwiseindicated, the terms “positioning reference signal” and “PRS” refer toany type of reference signal that can be used for positioning, such asbut not limited to, PRS signals in LTE, NRS in 5G, TRS, CRS, CSI-RS,SRS, etc.

FIG. 6 illustrates an exemplary call flow between a UE 204 and a networknode 630 for performing positioning operations, according to aspects ofthe disclosure. The network node 630 may be a non-serving gNB 222, anLMF 270, a location server 230, an emergency call center (e.g., a PSAP),or the like. As illustrated in FIG. 6, instead of the UE 204 initiatingpositioning operations, as in FIGS. 5A and 5B, the network node 630 mayinitiate positioning operations.

Specifically, at 602, the network node 630 queries the UE 204 forneighbor cell information. The network node 630 may tunnel the querythrough the serving gNB 222, or may send the query to the serving gNB222, which may relay it to the UE 204. At 604, the UE 204 can thenreport the same information to the network node 630 that was describedabove with reference to stage 502 of FIG. 5A. The UE 204 may simplyreply to the query with the requested information, or add its ownrequests in addition (e.g., a request for positioning referencesignaling from particular neighbor cells and/or TRPs, and/or a requestfor base station almanac information on particular neighbor cells and/orTRPs).

The call flow illustrated in FIG. 6 may replace the Request AssistanceData messages at 502 of FIG. 5A. Thus, although not shown in FIG. 6, theillustrated positioning method may begin with an exchange of capabilitymessages, similar to stages 402 and 404 of FIG. 4, and may continue withthe network node 630 sending Provide Assistance Data and RequestLocation Information messages to the UE 204 and the UE 204 respondingwith a Provide Location Information message, as described above withreference to stages 406 to 412 of FIG. 4 and 504 of FIG. 5A, but usingthe new information exchanged at 604.

LPP was designed for communication between the location server (e.g., anE-SMLC) and a UE 204. Specifically, the LPP messages illustrated in FIG.4 are routed through the UE's 204 serving eNB 224 in RRC messagescarrying NAS containers that the serving eNB 224 cannot read. However,in NR, the LMF 270 may be co-located with the serving gNB 222, raisingpotential issues.

FIG. 7 illustrates a conventional LPP acknowledgment call flow between aUE 204 and a location server 230. Each LPP message illustrated in FIG. 4may carry an acknowledgment request and/or an acknowledgment indicator.An LPP message that includes an acknowledgment request also includes asequence number. Upon reception of an LPP message that includes anacknowledgment request, the receiver returns an LPP message with anacknowledgment response for the sequence number of the message beingacknowledged. An acknowledgment response may contain no LPP message body(in which case only the sequence number being acknowledged issignificant). Alternatively, the acknowledgment may be sent in an LPPmessage along with an LPP message body. An acknowledgment is returnedfor each received LPP message that requested an acknowledgment includingany duplicate(s). Once a sender receives an acknowledgment for an LPPmessage, and provided any included sequence number is matching, it ispermitted to send the next LPP message. No message reordering is neededat the receiver since this stop-and-wait method of sending ensures thatmessages normally arrive in the correct order.

Thus, as illustrated in FIG. 7, at 702, the location server 230 sends anLPP message N (e.g., any of the LPP messages sent by the location server230 in FIG. 4) having a sequence number. At 704, if LPP message N isreceived and the UE 204 is able to decode it, the UE 204 returns anacknowledgment for message N. The acknowledgment contains an indicatorset to the same sequence number as that in message N. At 706, when theacknowledgment for LPP message N is received and the included sequenceindicator matches the sequence number sent in message N, the locationserver 230 sends the next LPP message N+1 (e.g., any subsequent LPPmessages sent by the location server 230 in FIG. 4) to the UE 204 whenthis message is available.

When an LPP message that requested acknowledgment is sent and notacknowledged, it is resent by the sender following a timeout period upto three times. If still unacknowledged after that, the sender abortsall LPP activity for the associated session. The timeout period isdetermined by the sender implementation. The above LPP acknowledgmentprocedure is known in the art and described in various publiclyavailable technical specifications from 3GPP (e.g., 3GPP TS 36.355).

FIG. 8 illustrates a conventional LPP retransmission call flow between aUE 204 and a location server 230. At 802, the location server 230 sendsan LPP message N (e.g., any of the LPP messages sent by the locationserver 230 in FIG. 4) to the UE 204 for a particular location sessionand includes a request for acknowledgment along with a sequence number.

At 804, if LPP message N is received and the UE 204 is able to determinethat an acknowledgment is requested and to decode the sequence number(regardless of whether the message body can be correctly decoded), theUE 204 returns an acknowledgment for message N. If the acknowledgment isreceived at the location server 230 (such that the acknowledged messagecan be identified and the sequence numbers are matching), the locationserver 230 skips stages 806 and 808.

However, at 806, if the acknowledgment from stage 804 is not receivedafter a timeout period, the location server 230 retransmits LPP messageN and includes the same sequence number as in stage 802.

At 808, if LPP message N in stage 806 is received and the UE 204 is ableto decode the acknowledgment request and the sequence number (regardlessof whether the message body can be correctly decoded and whether or notthe message is considered a duplicate), the UE 204 returns anacknowledgment. Stage 806 may be repeated one or more times if theacknowledgment in stage 808 is not received after a timeout period bythe location server 230. If the acknowledgment in stage 808 is still notreceived after sending three retransmissions, the location server 230aborts all procedures and activity associated with LPP support for theparticular location session.

At 810, once an acknowledgment in stage 804 or 808 is received, thelocation server 230 sends the next LPP message N+1 for the locationsession to the UE 204 when this message is available. The above LPPretransmission procedure is known in the art and described in variouspublicly available technical specifications from 3GPP (e.g., 3GPP TS36.355).

In the present disclosure, in an aspect, if the LMF 270 is co-locatedwith the serving gNB 222, the LMF 270 may still be a distinct softwareentity (such as a location measurement unit (LMU)) within the gNB 222,and as such, the same type of protocol as with LPP could be used. Thatis, the messages between the UE 204 and the LMF 270 could be tunneledthrough the gNB 222 without the gNB 222 being able to decode them. In avariation of this approach, LPP messages can be used with their“acknowledgment request” field either set to “not requested” or omittedaltogether with the understanding that omission implies thatacknowledgment is not requested. Further, the choice among the abovealternatives may be dependent on whether the gNB 222 with the integratedLMF 270 is a serving cell of the UE 204, or in particular, whether it isa primary serving cell of the UE 204. Omission of the “acknowledgmentrequest” field may save on some signaling overhead, because the gNB 222and the UE 204 may have other independent means to confirm whether theyreceived each other's LPP messages, for example, HARQ and/or RLCacknowledgments when the gNB 222 is a serving cell.

Alternatively, for lower latency, the LMF 270 may be tightly integratedinto the gNB 222. In that case, the use of an LPP-type protocol (likethe LPP procedures described above with reference to FIGS. 7 and 8) maycause extra overhead and latency. To address this issue, the techniquesdisclosed herein allow a mode in which direct RRC signaling between theserving gNB 222 and the UE 204 is used instead of an LPP-type protocolbetween the UE 204 and the LMF 270 or location server 230. For example,the LMF 270 and the UE 204 can use RRC with acknowledged mode as areplacement for the LPP acknowledgment and retransmission schemesdescribed above with reference to FIGS. 6 and 7.

Currently, LPP allows for aperiodic and periodic assistance datatransmission, which may be solicited by request, or unsolicited. FIG. 9illustrates a conventional LPP periodic assistance data transfer callflow between a UE 204 and a location server 230. This procedure enablesa target UE 204 to request a location server 230 to send assistance dataperiodically. At 902, the UE 204 sends a Request Assistance Data messageto the location server 230 using transaction ID “T1.” The messagecontains a periodic session ID “S” (different from any other periodicsession ID currently in use between the UE 204 and the location server230). The message also includes a positioning method specific assistancedata request element identifying the type of assistance data beingrequested together with the desired periodicity conditions for sendingit and a duration for ending the assistance data transfer.

At 904, the location server 230 responds with a Provide Assistance Datamessage to the UE 204. The Provide Assistance Data message uses thetransaction ID “T1” from stage 902 and indicates the end of thistransaction. The message contains the periodic session ID “S.” If therequest can be supported, the message contains the control parameters inthe positioning method specific assistance data, which may confirm orredefine the type of assistance data or periodicity parameters requestedat stage 902. If the UE 204 requested non-periodic assistance data inaddition to the periodic assistance data in stage 902, the ProvideAssistance Data message may also include the non-periodic assistancedata (but not any periodic assistance data).

If the request cannot be supported (either fully or partly), an errorreason is provided. If the request cannot even partly be supported, theremaining stages are not performed. Note that the UE 204 infers from anabsence of the periodic session ID that the location server 230 does notsupport periodic assistance data delivery. In that case, the UE 204 doesnot expect the subsequent data transaction (stages 906 to 914).

At 906, when the first periodic message is available, the locationserver 230 sends an unsolicited Provide Assistance Data message to theUE 204 containing the periodic Session ID “S” and the periodicassistance data confirmed in stage 904. The message uses some availabletransaction ID “T2” that may be different from “T1.”

At 908, the location server 230 may continue to send further ProvideAssistance Data messages to the UE 204 containing the periodicassistance data confirmed or redefined in stage 904 when each additionalperiodicity condition occurs. Note that the UE 204 expects a ProvideAssistance Data messages as in stage 904 at confirmed interval(s). Ifsome or all of the assistance data is not available at each periodicinterval, an error indication is provided.

At 910, if the UE 204 desires the session to end, the UE 204 sends anAbort message to the location server 230 for transaction “T2” that mayoptionally include an abort cause. The remaining stages are thenomitted.

At 912, if the location server 230 desires the session to end, thelocation server 230 sends an Abort message to the UE 204 for transaction“T2” that may optionally include an abort Cause. The remaining stagesare then omitted.

At 914, when the duration or other conditions for ending the periodicassistance data transfer occur, the last Provide Assistance Data messagetransferred indicates the end of transaction “T2.”

An assistance data delivery procedure is also defined for LPP and allowsthe location server 230 to provide unsolicited assistance data to the UE204. Specifically, the location server 230 sends a Provide AssistanceData message to the target UE 204 containing assistance data. If thereare no subsequent messages to send, this message indicates that it isthe last message of the transaction. However, if there will besubsequent messages, the location server 230 may transmit one or moreadditional Provide Assistance Data messages to the target UE 204containing additional assistance data. The last such message indicatesthat it is the last message of the transaction. The LPP periodicassistance data transfer procedure illustrated in FIG. 9 and theperiodic assistance data delivery procedure described above are known inthe art and described in various publicly available technicalspecifications from 3GPP (e.g., 3GPP TS 36.355).

In NR, there are occasional situations where assistance data should beupdated, but these situations do not occur at a regular periodicity.Rather, these updates may be based on various event triggers, such as areconfiguration of transmit beams, a mechanical control/change ofantenna tilt and/or height, and the like. They may also be caused bymultiple other factors, such as network loading, inter-cell interferencecoordination, etc. Currently, as described above with reference to FIG.9, assistance data is expected to be received at each periodic interval.If not, an error message is expected corresponding to an assistance datamessage if the data to generate that assistance data message was notavailable in time. However, this periodic reporting of assistance datais not necessary in NR given the aperiodic nature of the above-mentionedevent triggers.

Accordingly, the present disclosure provides techniques to allow aconfigurable period for sending assistance data messages to the UE 204.Specifically, each report of assistance data may have a validity timer,and the next report would be expected at the end of the timer.

FIG. 10 illustrates an exemplary method of providing assistance datafrom an LMF 270 to a UE 204, according to aspects of the disclosure. At1002, the UE 204 begins an assistance data session by sending a RequestAssistance Data message to the LMF 270, similar to 902 of FIG. 9. At1004, the LMF 270 responds with a Provide Assistance Data message to theUE 204, similar to 904 of FIG. 9. The Provide Assistance Data messagemay include a validity timer specifying a validity time period “X”during which the information in the Provide Assistance Data message sentat 1004 will be valid. Based on the validity timer, the UE 204 will notexpect another Provide Assistance Data message until the end of thevalidity time period “X.”

At 1006, at the end of the validity time period “X,” the LMF 270 sendsanother Provide Assistance Data message, this one including a validitytime period “Y” during which the information in the Provide AssistanceData message sent at 1006 will be valid. Provide Assistance Datamessages may have a large set of fields, and only a small subset mayhave changed from the previous Provide Assistance Data message. If allfields are optional, then only the fields that have new values need tobe sent. However, if there are mandatory fields that did not change, andare thus redundant, this can create unnecessary overhead and latency. Toaddress this, the present disclosure allows the LMF 270 to configure aset of possible combinations of values of the fields that are expectedto change. Each new Provide Assistance Data message need only indicatean index into this set. This set may be reconfigured and is valid forthe duration of the current irregularly-periodic assistance datasession.

At 1008, at the end of the validity time period “Y,” the LMF 270 sendsanother Provide Assistance Data message, this one including a validitytime period “Z” during which the information in the Provide AssistanceData message sent at 1008 will be valid. These irregularly-periodicProvide Assistance Data messages continue until either the UE 204 or theLMF 270 sends an Abort message, as at 910 and 912 of FIG. 9. When theduration or other conditions for ending the irregularly-periodicassistance data delivery session occur, the last Provide Assistance Datamessage transferred indicates the end of session, as at 914 of FIG. 9.

FIG. 11 illustrates an exemplary method for providing positioningassistance data to a UE, according to aspects of the disclosure. In anaspect, the method 1100 may be performed by the UE (e.g., any of the UEsdescribed herein).

At 1102, the UE optionally receives, from a positioning entity (e.g.,LMF 270, network node 630), a request for positioning capabilities ofthe UE, the request for positioning capabilities of the UE identifying apositioning procedure (e.g., OTDOA, RTT, UTDOA), as at 402 of FIG. 4. Inan aspect, operation 1102 may be performed by receiver(s) 312,processing system 332, memory 340, and/or assistance data module 342,any or all of which may be considered means for performing thisoperation.

At 1104, the UE optionally sends, to the positioning entity,capabilities of the UE to support the positioning procedure, as at 404of FIG. 4. In an aspect, operation 1104 may be performed bytransmitter(s) 314, processing system 332, memory 340, and/or assistancedata module 342, any or all of which may be considered means forperforming this operation.

At 1106, the UE transmits, to the positioning entity, a request forpositioning assistance data message, the request for positioningassistance data message identifying a serving cell (e.g., serving gNB222) of the UE and one or more neighboring cells of the UE with whichthe UE is attempting to perform a positioning procedure, as at 502 and512 of FIGS. 5A and 5B, respectively. In an aspect, operation 1106 maybe performed by transmitter(s) 314, processing system 332, memory 340,and/or assistance data module 342, any or all of which may be consideredmeans for performing this operation.

At 1108, the UE receives, from the positioning entity, a positioningassistance data message in response to the request at 1106. In anaspect, the positioning assistance data message may include at leastpositioning reference signal (e.g., PRS) configurations for the servingcell and the one or more neighboring cells identified in the request forpositioning assistance data message, as at 504 and 514 of FIGS. 5A and5B, respectively. In an aspect, operation 1108 may be performed byreceiver(s) 312, processing system 332, memory 340, and/or assistancedata module 342, any or all of which may be considered means forperforming this operation.

At 1110, the UE optionally receives, from the positioning entity, arequest for location information for the UE, as at 408 of FIG. 4. In anaspect, operation 1110 may be performed by receiver(s) 312, processingsystem 332, memory 340, and/or assistance data module 342, any or all ofwhich may be considered means for performing this operation.

At 1112, the UE optionally measures, in response to reception of therequest for location information, RSTD measurements between pairs of theserving cell and the one or more neighboring cells, as at 410 of FIG. 4.In an aspect, operation 1112 may be performed by WWAN transceiver 310,processing system 332, memory 340, and/or assistance data module 342,any or all of which may be considered means for performing thisoperation.

At 1114, the UE optionally sends the RSTD measurements to thepositioning entity, as at 412 of FIG. 4. In an aspect, operation 1114may be performed by transmitter(s) 314, processing system 332, memory340, and/or assistance data module 342, any or all of which may beconsidered means for performing this operation.

FIG. 12 illustrates an exemplary method 1200 for performing positioningassistance operations, according to aspects of the disclosure. In anaspect, the method 1200 may be performed by a positioning entity (e.g.,location server 230, LMF 270, serving gNB 222, network node 630).

At 1202, the positioning entity receives, from a UE (e.g., any of theUEs described herein), a request for positioning assistance datamessage, the request for positioning assistance data message identifyinga serving cell of the UE and one or more neighboring cells of the UEwith which the UE is attempting to perform a positioning procedure. Inan aspect, where the positioning entity is a location server or othernetwork entity, operation 1202 may be performed by network interface(s)390, processing system 394, memory 396, and/or assistance data module398, any or all of which may be considered means for performing thisoperation. In an aspect, where the positioning entity is a component ormodule of a base station (e.g., gNB 222), operation 1202 may beperformed by receiver(s) 352, processing system 384, memory 386, and/orassistance data module 388, any or all of which may be considered meansfor performing this operation.

At 1204, the positioning entity transmits, to the UE, a positioningassistance data message in response to the request. In an aspect, wherethe positioning entity is a location server or other network entity,operation 1204 may be performed by network interface(s) 390, processingsystem 394, memory 396, and/or assistance data module 398, any or all ofwhich may be considered means for performing this operation. In anaspect, where the positioning entity is a component or module of a basestation (e.g., gNB 222), operation 1204 may be performed bytransmitter(s) 354, processing system 384, memory 386, and/or assistancedata module 388, any or all of which may be considered means forperforming this operation.

As will be appreciated, the above techniques reduce the overhead ofsending assistance data to a UE (e.g., UE 204).

Those of skill in the art will appreciate that information and signalsmay be represented using any of a variety of different technologies andtechniques. For example, data, instructions, commands, information,signals, bits, symbols, and chips that may be referenced throughout theabove description may be represented by voltages, currents,electromagnetic waves, magnetic fields or particles, optical fields orparticles, or any combination thereof.

Further, those of skill in the art will appreciate that the variousillustrative logical blocks, modules, circuits, and algorithm stepsdescribed in connection with the aspects disclosed herein may beimplemented as electronic hardware, computer software, or combinationsof both. To clearly illustrate this interchangeability of hardware andsoftware, various illustrative components, blocks, modules, circuits,and steps have been described above generally in terms of theirfunctionality. Whether such functionality is implemented as hardware orsoftware depends upon the particular application and design constraintsimposed on the overall system. Skilled artisans may implement thedescribed functionality in varying ways for each particular application,but such implementation decisions should not be interpreted as causing adeparture from the scope of the present disclosure.

The various illustrative logical blocks, modules, and circuits describedin connection with the aspects disclosed herein may be implemented orperformed with a general purpose processor, a DSP, an ASIC, an FPGA, orother programmable logic device, discrete gate or transistor logic,discrete hardware components, or any combination thereof designed toperform the functions described herein. A general purpose processor maybe a microprocessor, but in the alternative, the processor may be anyconventional processor, controller, microcontroller, or state machine. Aprocessor may also be implemented as a combination of computing devices,e.g., a combination of a DSP and a microprocessor, a plurality ofmicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration.

The methods, sequences and/or algorithms described in connection withthe aspects disclosed herein may be embodied directly in hardware, in asoftware module executed by a processor, or in a combination of the two.A software module may reside in random access memory (RAM), flashmemory, read-only memory (ROM), erasable programmable ROM (EPROM),electrically erasable programmable ROM (EEPROM), registers, hard disk, aremovable disk, a CD-ROM, or any other form of storage medium known inthe art. An exemplary storage medium is coupled to the processor suchthat the processor can read information from, and write information to,the storage medium. In the alternative, the storage medium may beintegral to the processor. The processor and the storage medium mayreside in an ASIC. The ASIC may reside in a user terminal (e.g., UE). Inthe alternative, the processor and the storage medium may reside asdiscrete components in a user terminal.

In one or more exemplary aspects, the functions described may beimplemented in hardware, software, firmware, or any combination thereof.If implemented in software, the functions may be stored on ortransmitted over as one or more instructions or code on acomputer-readable medium. Computer-readable media includes both computerstorage media and communication media including any medium thatfacilitates transfer of a computer program from one place to another. Astorage media may be any available media that can be accessed by acomputer. By way of example, and not limitation, such computer-readablemedia can comprise RAM, ROM, EEPROM, CD-ROM or other optical diskstorage, magnetic disk storage or other magnetic storage devices, or anyother medium that can be used to carry or store desired program code inthe form of instructions or data structures and that can be accessed bya computer. Also, any connection is properly termed a computer-readablemedium. For example, if the software is transmitted from a website,server, or other remote source using a coaxial cable, fiber optic cable,twisted pair, digital subscriber line (DSL), or wireless technologiessuch as infrared, radio, and microwave, then the coaxial cable, fiberoptic cable, twisted pair, DSL, or wireless technologies such asinfrared, radio, and microwave are included in the definition of medium.Disk and disc, as used herein, includes compact disc (CD), laser disc,optical disc, digital versatile disc (DVD), floppy disk and Blu-ray discwhere disks usually reproduce data magnetically, while discs reproducedata optically with lasers. Combinations of the above should also beincluded within the scope of computer-readable media.

While the foregoing disclosure shows illustrative aspects of thedisclosure, it should be noted that various changes and modificationscould be made herein without departing from the scope of the disclosureas defined by the appended claims. The functions, steps and/or actionsof the method claims in accordance with the aspects of the disclosuredescribed herein need not be performed in any particular order.Furthermore, although elements of the disclosure may be described orclaimed in the singular, the plural is contemplated unless limitation tothe singular is explicitly stated.

What is claimed is:
 1. A method for performing positioning assistanceoperations at a user equipment (UE), the method comprising:transmitting, to a positioning entity, a request for positioningassistance data message, the request for positioning assistance datamessage identifying a serving cell of the UE and one or more neighboringcells of the UE with which the UE is attempting to perform a positioningprocedure, wherein the positioning entity is separate from the servingcell, and wherein the request for positioning assistance data message istransmitted to the positioning entity via the serving cell; andreceiving, from the positioning entity, a positioning assistance datamessage in response to the request.
 2. The method of claim 1, whereinthe positioning assistance data message includes at least positioningreference signal configurations for the serving cell and the one or moreneighboring cells identified in the request for positioning assistancedata message.
 3. The method of claim 1, wherein the request forpositioning assistance data message further includes a signal strengthat the UE of each of the one or more neighboring cells.
 4. The method ofclaim 3, wherein the signal strength of each of the one or moreneighboring cells is determined from a synchronization signal block(SSB), channel state information reference signal (CSI-RS), orpositioning reference signal (PRS) of the neighboring cell.
 5. Themethod of claim 1, wherein the request for positioning assistance datamessage further includes a request that the one or more neighboringcells transmit positioning reference signals to the UE.
 6. The method ofclaim 1, wherein the request for positioning assistance data messagefurther includes a request for base station almanac information for eachof the one or more neighboring cells.
 7. The method of claim 6, whereinthe base station almanac information comprises a geographic location ofan antenna array of each neighboring cell of the one or more neighboringcells, an orientation, tilt, and height of the antenna array, an antennaand beam pattern, an extent to which the neighboring cell issynchronized with the serving cell, an extent to which a neighboringcell group-delay is calibrated, or any combination thereof.
 8. Themethod of claim 1, wherein the serving cell and the one or moreneighboring cells are identified in the positioning assistance datamessage by an index value corresponding to their position in the requestfor positioning assistance data message.
 9. The method of claim 1,wherein the request for positioning assistance data message is decodedby the serving cell and forwarded to the positioning entity via NewRadio (NR) positioning protocol type A (NRPPa) or Long-Term Evolution(LTE) positioning protocol type A (LPPa).
 10. The method of claim 1,wherein the positioning entity is a component of the serving cell. 11.The method of claim 10, wherein the request for positioning assistancedata message is transmitted to and the positioning assistance datamessage is received from the positioning entity of the serving cellusing radio resource control (RRC) signaling.
 12. The method of claim10, wherein the request for positioning assistance data message istransmitted to and the positioning assistance data message is receivedfrom the positioning entity of the serving cell using medium accesscontrol control elements (MAC-CEs), downlink control information (DCI),or both.
 13. The method of claim 1, further comprising: receiving, fromthe positioning entity, a request for positioning capabilities of theUE, the request for positioning capabilities of the UE identifying thepositioning procedure; and transmitting, to the positioning entity,capabilities of the UE to support the positioning procedure.
 14. Themethod of claim 1, further comprising: receiving, from the positioningentity, a request for information about the one or more neighboringcells, wherein the UE transmits the request for positioning assistancedata message in response to reception of the request for informationabout the one or more neighboring cells.
 15. The method of claim 1,wherein the positioning assistance data message includes a validity timefield indicating a time period during which information in thepositioning assistance data message will be valid.
 16. The method ofclaim 15, wherein a subsequent positioning assistance data message isexpected at an end of the time period in the validity time field. 17.The method of claim 15, wherein the positioning assistance data messageonly includes information fields that have changed since a most recentpositioning assistance data message from the positioning entity.
 18. Themethod of claim 15, wherein the positioning assistance data message onlyincludes an index to a set of information fields that are expected tochange across positioning assistance data messages from the positioningentity.
 19. The method of claim 18, wherein the index is configured foreach positioning session between the positioning entity and the UE. 20.The method of claim 1, wherein the positioning entity comprises alocation management function (LMF).
 21. A method for performingpositioning assistance operations at a positioning entity, the methodcomprising: receiving, from a user equipment (UE), a request forpositioning assistance data message, the request for positioningassistance data message identifying a serving cell of the UE and one ormore neighboring cells of the UE with which the UE is attempting toperform a positioning procedure, wherein the positioning entity isseparate from the serving cell, and wherein the request for positioningassistance data message is received from the UE via the serving cell;and transmitting, to the UE, a positioning assistance data message inresponse to the request.
 22. The method of claim 21, wherein thepositioning assistance data message includes at least positioningreference signal configurations for the serving cell and the one or moreneighboring cells identified in the request for positioning assistancedata message.
 23. The method of claim 21, wherein the request forpositioning assistance data message further includes a signal strengthat the UE of each of the one or more neighboring cells.
 24. The methodof claim 23, wherein the signal strength of each of the one or moreneighboring cells is determined from a synchronization signal block(SSB), channel state information reference signal (CSI-RS), orpositioning reference signal (PRS) of the neighboring cell.
 25. Themethod of claim 21, wherein the request for positioning assistance datamessage further includes a request that the one or more neighboringcells transmit positioning reference signals to the UE.
 26. The methodof claim 21, wherein the request for positioning assistance data messagefurther includes a request for base station almanac information for eachof the one or more neighboring cells.
 27. The method of claim 26,wherein the base station almanac information comprises a geographiclocation of an antenna array of each neighboring cell of the one or moreneighboring cells, an orientation, tilt, and height of the antennaarray, an antenna and beam pattern, an extent to which the neighboringcell is synchronized with the serving cell, an extent to which aneighboring cell group-delay is calibrated, or any combination thereof.28. The method of claim 21, wherein the serving cell and the one or moreneighboring cells are identified in the positioning assistance datamessage by an index value corresponding to their position in the requestfor positioning assistance data message.
 29. The method of claim 21,wherein the request for positioning assistance data message is decodedby the serving cell, and wherein the request for positioning assistancedata message is received from the serving cell via New Radio (NR)positioning protocol type A (NRPPa) or Long-Term Evolution (LTE)positioning protocol type A (LPPa).
 30. The method of claim 21, whereinthe positioning entity is a component of the serving cell.
 31. Themethod of claim 30, wherein the request for positioning assistance datamessage is received from and the positioning assistance data message istransmitted to the UE using radio resource control (RRC) signaling. 32.The method of claim 30, wherein the request for positioning assistancedata message is received from and the positioning assistance datamessage is transmitted to the UE using medium access control controlelements (MAC-CEs), downlink control information (DCI), or both.
 33. Themethod of claim 21, further comprising: transmitting, to the UE, arequest for positioning capabilities of the UE, the request forpositioning capabilities of the UE identifying the positioningprocedure; and receiving, from the UE, capabilities of the UE to supportthe positioning procedure.
 34. The method of claim 21, furthercomprising: transmitting, to the UE, a request for information about theone or more neighboring cells, wherein the UE transmits the request forpositioning assistance data message in response to reception of therequest for information about the one or more neighboring cells.
 35. Themethod of claim 21, wherein the positioning assistance data messageincludes a validity time field indicating a time period during whichinformation in the positioning assistance data message will be valid.36. The method of claim 35, wherein a subsequent positioning assistancedata message is expected at an end of the time period in the validitytime field.
 37. The method of claim 35, wherein the positioningassistance data message only includes information fields that havechanged since a most recent positioning assistance data message from thepositioning entity.
 38. The method of claim 35, wherein the positioningassistance data message only includes an index to a set of informationfields that are expected to change across positioning assistance datamessages from the positioning entity.
 39. The method of claim 38,wherein the index is configured for each positioning session between thepositioning entity and the UE.
 40. The method of claim 21, wherein thepositioning entity comprises a location management function (LMF).
 41. Auser equipment (UE), comprising: a memory; at least one transceiver; andat least one processor communicatively coupled to the memory and the atleast one transceiver, the at least one processor configured to: causethe at least one transceiver to transmit, to a positioning entity, arequest for positioning assistance data message, the request forpositioning assistance data message identifying a serving cell of the UEand one or more neighboring cells of the UE with which the UE isattempting to perform a positioning procedure, wherein the positioningentity is separate from the serving cell, and wherein the UE transmitsthe request for positioning assistance data message to the positioningentity via the serving cell; and receive, from the positioning entityvia the at least one transceiver, a positioning assistance data messagein response to the request.
 42. The UE of claim 41, wherein thepositioning assistance data message includes at least positioningreference signal configurations for the serving cell and the one or moreneighboring cells identified in the request for positioning assistancedata message.
 43. The UE of claim 41, wherein the request forpositioning assistance data message further includes a signal strengthat the UE of each of the one or more neighboring cells.
 44. The UE ofclaim 43, wherein the signal strength of each of the one or moreneighboring cells is determined from a synchronization signal block(SSB), channel state information reference signal (CSI-RS), orpositioning reference signal (PRS) of the neighboring cell.
 45. The UEof claim 41, wherein the request for positioning assistance data messagefurther includes a request that the one or more neighboring cellstransmit positioning reference signals to the UE.
 46. The UE of claim41, wherein the request for positioning assistance data message furtherincludes a request for base station almanac information for each of theone or more neighboring cells.
 47. The UE of claim 46, wherein the basestation almanac information comprises a geographic location of anantenna array of each neighboring cell of the one or more neighboringcells, an orientation, tilt, and height of the antenna array, an antennaand beam pattern, an extent to which the neighboring cell issynchronized with the serving cell, an extent to which a neighboringcell group-delay is calibrated, or any combination thereof.
 48. The UEof claim 41, wherein the serving cell and the one or more neighboringcells are identified in the positioning assistance data message by anindex value corresponding to their position in the request forpositioning assistance data message.
 49. The UE of claim 41, wherein therequest for positioning assistance data message is decoded by theserving cell and forwarded to the positioning entity via New Radio (NR)positioning protocol type A (NRPPa) or Long-Term Evolution (LTE)positioning protocol type A (LPPa).
 50. The UE of claim 41, wherein thepositioning entity is a component of the serving cell.
 51. The UE ofclaim 50, wherein the UE communicates with the positioning entity of theserving cell using radio resource control (RRC) signaling.
 52. The UE ofclaim 50, wherein the UE communicates with the positioning entity of theserving cell using medium access control control elements (MAC-CEs),downlink control information (DCI), or both.
 53. The UE of claim 41,wherein the at least one processor is further configured to: receive,from the positioning entity via the at least one transceiver, a requestfor positioning capabilities of the UE, the request for positioningcapabilities of the UE identifying the positioning procedure; and causethe at least one transceiver to transmit, to the positioning entity,capabilities of the UE to support the positioning procedure.
 54. The UEof claim 41, wherein the at least one processor is further configuredto: receive, from the positioning entity via the at least onetransceiver, a request for information about the one or more neighboringcells, wherein the UE transmits the request for positioning assistancedata message in response to reception of the request for informationabout the one or more neighboring cells.
 55. The UE of claim 41, whereinthe positioning assistance data message includes a validity time fieldindicating a time period during which information in the positioningassistance data message will be valid.
 56. The UE of claim 55, wherein asubsequent positioning assistance data message is expected at an end ofthe time period in the validity time field.
 57. The UE of claim 55,wherein the positioning assistance data message only includesinformation fields that have changed since a most recent positioningassistance data message from the positioning entity.
 58. The UE of claim55, wherein the positioning assistance data message only includes anindex to a set of information fields that are expected to change acrosspositioning assistance data messages from the positioning entity. 59.The UE of claim 58, wherein the index is configured for each positioningsession between the positioning entity and the UE.
 60. The UE of claim41, wherein the positioning entity comprises a location managementfunction (LMF).
 61. A positioning entity, comprising: a memory; acommunication device; and at least one processor communicatively coupledto the memory and the communication device, the at least one processorconfigured to: receive, from a user equipment (UE) via the communicationdevice, a request for positioning assistance data message, the requestfor positioning assistance data message identifying a serving cell ofthe UE and one or more neighboring cells of the UE with which the UE isattempting to perform a positioning procedure, wherein the positioningentity is separate from the serving cell, and wherein the positioningentity receives the request for positioning assistance data message fromthe UE via the serving cell; and cause the communication device totransmit, to the UE, a positioning assistance data message in responseto the request.
 62. The positioning entity of claim 61, wherein thepositioning assistance data message includes at least positioningreference signal configurations for the serving cell and the one or moreneighboring cells identified in the request for positioning assistancedata message.
 63. The positioning entity of claim 61, wherein therequest for positioning assistance data message further includes asignal strength at the UE of each of the one or more neighboring cells.64. The positioning entity of claim 63, wherein the signal strength ofeach of the one or more neighboring cells is determined from asynchronization signal block (SSB), channel state information referencesignal (CSI-RS), or positioning reference signal (PRS) of theneighboring cell.
 65. The positioning entity of claim 61, wherein therequest for positioning assistance data message further includes arequest that the one or more neighboring cells transmit positioningreference signals to the UE.
 66. The positioning entity of claim 61,wherein the request for positioning assistance data message furtherincludes a request for base station almanac information for each of theone or more neighboring cells.
 67. The positioning entity of claim 66,wherein the base station almanac information comprises a geographiclocation of an antenna array of each neighboring cell of the one or moreneighboring cells, an orientation, tilt, and height of the antennaarray, an antenna and beam pattern, an extent to which the neighboringcell is synchronized with the serving cell, an extent to which aneighboring cell group-delay is calibrated, or any combination thereof.68. The positioning entity of claim 61, wherein the serving cell and theone or more neighboring cells are identified in the positioningassistance data message by an index value corresponding to theirposition in the request for positioning assistance data message.
 69. Thepositioning entity of claim 61, wherein the request for positioningassistance data message is decoded by the serving cell, and wherein therequest for positioning assistance data message is received from theserving cell via New Radio (NR) positioning protocol type A (NRPPa) orLong-Term Evolution (LTE) positioning protocol type A (LPPa).
 70. Thepositioning entity of claim 61, wherein the positioning entity is acomponent of the serving cell, and wherein the communication devicecomprises at least one transceiver.
 71. The positioning entity of claim70, wherein the positioning entity communicates with the UE using radioresource control (RRC) signaling.
 72. The positioning entity of claim70, wherein the positioning entity communicates with the UE using mediumaccess control control elements (MAC-CEs), downlink control information(DCI), or both.
 73. The positioning entity of claim 61, wherein the atleast one processor is further configured to: cause the communicationdevice to transmit, to the UE, a request for positioning capabilities ofthe UE, the request for positioning capabilities of the UE identifyingthe positioning procedure; and receive, from the UE via thecommunication device, capabilities of the UE to support the positioningprocedure.
 74. The positioning entity of claim 61, wherein the at leastone processor is further configured to: cause the communication deviceto transmit, to the UE, a request for information about the one or moreneighboring cells, wherein the UE transmits the request for positioningassistance data message in response to reception of the request forinformation about the one or more neighboring cells.
 75. The positioningentity of claim 61, wherein the positioning assistance data messageincludes a validity time field indicating a time period during whichinformation in the positioning assistance data message will be valid.76. The positioning entity of claim 75, wherein a subsequent positioningassistance data message is expected at an end of the time period in thevalidity time field.
 77. The positioning entity of claim 75, wherein thepositioning assistance data message only includes information fieldsthat have changed since a most recent positioning assistance datamessage from the positioning entity.
 78. The positioning entity of claim75, wherein the positioning assistance data message only includes anindex to a set of information fields that are expected to change acrosspositioning assistance data messages from the positioning entity. 79.The positioning entity of claim 78, wherein the index is configured foreach positioning session between the positioning entity and the UE. 80.The positioning entity of claim 61, wherein the positioning entitycomprises a location management function (LMF), and wherein thecommunication device comprises at least one network interface.
 81. Auser equipment (UE), comprising: means for transmitting, to apositioning entity, a request for positioning assistance data message,the request for positioning assistance data message identifying aserving cell of the UE and one or more neighboring cells of the UE withwhich the UE is attempting to perform a positioning procedure, whereinthe positioning entity is separate from the serving cell, and whereinthe UE transmits the request for positioning assistance data message tothe positioning entity via the serving cell; and means for receiving,from the positioning entity, a positioning assistance data message inresponse to the request.
 82. A positioning entity, comprising: means forreceiving, from a user equipment (UE), a request for positioningassistance data message, the request for positioning assistance datamessage identifying a serving cell of the UE and one or more neighboringcells of the UE with which the UE is attempting to perform a positioningprocedure, wherein the positioning entity is separate from the servingcell, and wherein the positioning entity receives the request forpositioning assistance data message from the UE via the serving cell;and means for transmitting, to the UE, a positioning assistance datamessage in response to the request.
 83. A non-transitorycomputer-readable medium storing computer-executable instructions, thecomputer-executable instructions comprising: at least one instructioninstructing a user equipment (UE) to transmit, to a positioning entity,a request for positioning assistance data message, the request forpositioning assistance data message identifying a serving cell of the UEand one or more neighboring cells of the UE with which the UE isattempting to perform a positioning procedure, wherein the positioningentity is separate from the serving cell, and wherein the UE transmitsthe request for positioning assistance data message to the positioningentity via the serving cell; and at least one instruction instructingthe UE to receive, from the positioning entity, a positioning assistancedata message in response to the request.
 84. A non-transitorycomputer-readable medium storing computer-executable instructions, thecomputer-executable instructions comprising: at least one instructioninstructing a positioning entity to receive, from a user equipment (UE),a request for positioning assistance data message, the request forpositioning assistance data message identifying a serving cell of the UEand one or more neighboring cells of the UE with which the UE isattempting to perform a positioning procedure, wherein the positioningentity is separate from the serving cell, and wherein the positioningentity receives the request for positioning assistance data message fromthe UE via the serving cell; and at least one instruction instructingthe positioning entity to transmit, to the UE, a positioning assistancedata message in response to the request.
 85. A method for performingpositioning assistance operations at a user equipment (UE), the methodcomprising: transmitting, to a positioning entity, a request forpositioning assistance data message, the request for positioningassistance data message identifying a serving cell of the UE and one ormore neighboring cells of the UE with which the UE is attempting toperform a positioning procedure, wherein the request for positioningassistance data message further includes a request that the one or moreneighboring cells transmit positioning reference signals to the UE; andreceiving, from the positioning entity, a positioning assistance datamessage in response to the request.
 86. The method of claim 85, whereinthe request for positioning assistance data message further includes arequest for base station almanac information for each of the one or moreneighboring cells.
 87. The method of claim 85, wherein the positioningentity is a component of the serving cell.
 88. The method of claim 85,wherein the positioning entity is separate from the serving cell, andwherein the UE transmits the request for positioning assistance datamessage to the positioning entity via the serving cell.
 89. The methodof claim 85, further comprising: receiving, from the positioning entity,a request for information about the one or more neighboring cells,wherein the UE transmits the request for positioning assistance datamessage in response to reception of the request for information aboutthe one or more neighboring cells.
 90. The method of claim 85, whereinthe positioning assistance data message includes a validity time fieldindicating a time period during which information in the positioningassistance data message will be valid.
 91. A method for performingpositioning assistance operations at a positioning entity, the methodcomprising: receiving, from a user equipment (UE), a request forpositioning assistance data message, the request for positioningassistance data message identifying a serving cell of the UE and one ormore neighboring cells of the UE with which the UE is attempting toperform a positioning procedure, wherein the request for positioningassistance data message further includes a request that the one or moreneighboring cells transmit positioning reference signals to the UE; andtransmitting, to the UE, a positioning assistance data message inresponse to the request.
 92. The method of claim 91, wherein the requestfor positioning assistance data message further includes a request forbase station almanac information for each of the one or more neighboringcells.
 93. The method of claim 91, wherein the positioning entity is acomponent of the serving cell.
 94. The method of claim 91, wherein thepositioning entity is separate from the serving cell, and wherein thepositioning entity receives the request for positioning assistance datamessage from the UE via the serving cell.
 95. The method of claim 91,further comprising: transmitting, to the UE, a request for informationabout the one or more neighboring cells, wherein the UE transmits therequest for positioning assistance data message in response to receptionof the request for information about the one or more neighboring cells.96. The method of claim 91, wherein the positioning assistance datamessage includes a validity time field indicating a time period duringwhich information in the positioning assistance data message will bevalid.
 97. A user equipment (UE), comprising: a memory; at least onetransceiver; and at least one processor communicatively coupled to thememory and the at least one transceiver, the at least one processorconfigured to: cause the at least one transceiver to transmit, to apositioning entity, a request for positioning assistance data message,the request for positioning assistance data message identifying aserving cell of the UE and one or more neighboring cells of the UE withwhich the UE is attempting to perform a positioning procedure, whereinthe request for positioning assistance data message further includes arequest that the one or more neighboring cells transmit positioningreference signals to the UE; and receive, from the positioning entityvia the at least one transceiver, a positioning assistance data messagein response to the request.
 98. The UE of claim 97, wherein the requestfor positioning assistance data message further includes a request forbase station almanac information for each of the one or more neighboringcells.
 99. The UE of claim 97, wherein the positioning entity is acomponent of the serving cell.
 100. The UE of claim 97, wherein thepositioning entity is separate from the serving cell, and wherein the UEtransmits the request for positioning assistance data message to thepositioning entity via the serving cell.
 101. The UE of claim 97,wherein the at least one processor is further configured to: receive,from the positioning entity via the at least one transceiver, a requestfor information about the one or more neighboring cells, wherein the UEtransmits the request for positioning assistance data message inresponse to reception of the request for information about the one ormore neighboring cells.
 102. The UE of claim 97, wherein the positioningassistance data message includes a validity time field indicating a timeperiod during which information in the positioning assistance datamessage will be valid.
 103. A positioning entity, comprising: a memory;a communication device; and at least one processor communicativelycoupled to the memory and the communication device, the at least oneprocessor configured to: receive, from a user equipment (UE) via thecommunication device, a request for positioning assistance data message,the request for positioning assistance data message identifying aserving cell of the UE and one or more neighboring cells of the UE withwhich the UE is attempting to perform a positioning procedure, whereinthe request for positioning assistance data message further includes arequest that the one or more neighboring cells transmit positioningreference signals to the UE; and cause the communication device totransmit, to the UE, a positioning assistance data message in responseto the request.
 104. The positioning entity of claim 103, wherein therequest for positioning assistance data message further includes arequest for base station almanac information for each of the one or moreneighboring cells.
 105. The positioning entity of claim 103, wherein thepositioning entity is a component of the serving cell.
 106. Thepositioning entity of claim 103, wherein the positioning entity isseparate from the serving cell, and wherein the positioning entityreceives the request for positioning assistance data message from the UEvia the serving cell.
 107. The positioning entity of claim 103, whereinthe at least one processor is further configured to: cause thecommunication device to transmit, to the UE, a request for informationabout the one or more neighboring cells, wherein the UE transmits therequest for positioning assistance data message in response to receptionof the request for information about the one or more neighboring cells.108. The positioning entity of claim 103, wherein the positioningassistance data message includes a validity time field indicating a timeperiod during which information in the positioning assistance datamessage will be valid.
 109. A user equipment (UE), comprising: means fortransmitting, to a positioning entity, a request for positioningassistance data message, the request for positioning assistance datamessage identifying a serving cell of the UE and one or more neighboringcells of the UE with which the UE is attempting to perform a positioningprocedure, wherein the request for positioning assistance data messagefurther includes a request that the one or more neighboring cellstransmit positioning reference signals to the UE; and means forreceiving, from the positioning entity, a positioning assistance datamessage in response to the request.
 110. A positioning entity,comprising: means for receiving, from a user equipment (UE), a requestfor positioning assistance data message, the request for positioningassistance data message identifying a serving cell of the UE and one ormore neighboring cells of the UE with which the UE is attempting toperform a positioning procedure, wherein the request for positioningassistance data message further includes a request that the one or moreneighboring cells transmit positioning reference signals to the UE; andmeans for transmitting, to the UE, a positioning assistance data messagein response to the request.
 111. A non-transitory computer-readablemedium storing computer-executable instructions, the computer-executableinstructions comprising: at least one instruction instructing a userequipment (UE) to transmit, to a positioning entity, a request forpositioning assistance data message, the request for positioningassistance data message identifying a serving cell of the UE and one ormore neighboring cells of the UE with which the UE is attempting toperform a positioning procedure, wherein the request for positioningassistance data message further includes a request that the one or moreneighboring cells transmit positioning reference signals to the UE; andat least one instruction instructing the UE to receive, from thepositioning entity, a positioning assistance data message in response tothe request.
 112. A non-transitory computer-readable medium storingcomputer-executable instructions, the computer-executable instructionscomprising: at least one instruction instructing a positioning entity toreceive, from a user equipment (UE), a request for positioningassistance data message, the request for positioning assistance datamessage identifying a serving cell of the UE and one or more neighboringcells of the UE with which the UE is attempting to perform a positioningprocedure, wherein the request for positioning assistance data messagefurther includes a request that the one or more neighboring cellstransmit positioning reference signals to the UE; and at least oneinstruction instructing the positioning entity to transmit, to the UE, apositioning assistance data message in response to the request.